More than 300 rivers drain into Siberia's Lake Baikal, which holds 20

Hi Can anyone explain to me why Option B is wrong.

How do we say that comparison of amount of water is right in choice A]

''holds 20 percent of the world's fresh water, more than all the North American Great Lakes combined.'' looks like the comparison is b/w 20% of fresh water and other lakes.

I don't see a mention of ''all great lakes WATER combined''

How do we say that comparison of amount of water is right in choice A]

''holds 20 percent of the world's fresh water, more than all the North American Great Lakes combined.'' looks like the comparison is b/w 20% of fresh water and other lakes.

I don't see a mention of ''all great lakes WATER combined''

More than 300 rivers drain into Siberia's Lake Baikal, which holds 20 percent of the world's fresh water, more than all the North American Great Lakes combined.


(A) More than 300 rivers drain into Siberia's Lake Baikal, which holds 20 percent of the world's fresh water, more than all the North American Great Lakes combined.

(B) With 20 percent of the world's fresh water, that is more than all the North American Great Lakes combined, Siberia's Lake Baikal has more than 300 rivers that drain into it.

(C) Siberia's Lake Baikal, with more than 300 rivers draining into it, it holds more of the world's fresh water than all that of the North American Great Lakes combined, 20 percent.

(D) While more than 300 rivers drain into it, Siberia's lake Baikal holds 20 percent of the world's fresh water, which is more than all the North American Great Lakes combined.

(E) More than all the North American Great Lakes combined, Siberia's Lake Baikal, with more than 300 rivers draining into it, holds 20 percent of the world's fresh water.

Yeah, this is what makes comparisons so maddening. Two ways to think about it:

1) Sometimes the verb in a comparison is implied. If I write, "Tim runs faster than Mike," it's clear that we're comparing how fast Tim runs to how fast Mike runs, even if the second verb isn't stated. So we could interpret the construction in (A) to compare the amount of water Lake Baikal holds to the amount all the North American Great Lakes hold, even if the second "hold" is only implied.

2) And if your objection is that you'd like see the word "water" in the second part of the comparison, well, lakes are water, right? If we compare the amount of water in Lake Baikal to other lakes, what else could we possibly mean, other than the amount of water in those lakes? A lake without water isn't a lake! In essence, we're comparing water to water. That seems okay.

All to say, comparisons cause plenty of brain cramps for good reason. We can make ourselves crazy trying to figure out if something is implied or if a given comparison, if taken literally, is logical.

So simplify the process. When you see, "20 percent of the world's fresh water, more than all the North American Great Lakes combined," ask yourself if the portion in blue logically could modify the part in red. If you think it's fine, keep it. And if you find yourself going in circles wondering whether you can compare an amount of water to lakes, which are themselves water, keep it.

Initially, you're only looking for stuff that's definitively wrong. If you've got one comparison you're unsure about, and four other answer choices that all have concrete errors, well, an uncertain comparison it will have to be.

The takeaway: you're not going to have 100% confidence about every SC issue you see. No one does, including (*cough*) tutors with perfect GMAT scores. So be clear about how you set your priorities: concrete issues first; then the murky stuff.

I hope that helps!

I have a doubt here.
Which is a non-vital modifier, (when dropped, it does not change the meaning of the sentence). But here it is stating a very important fact that the Siberia's Lake Baikal holds 20 percent of the world's fresh water. So, why is it correct to use which over here?

For some reason, a large percentage of my students hate this question with the fury of a thousand suns. But you’ll love it… right?


I don’t really see any problems with (A). The “which” jumps out at me, but that seems fine, since “which holds 20% of the world’s fresh water” logically modifies “Siberia’s Lake Baikal.” That last modifier seems fine, too: “more than all the North American Great Lakes combined” describes “20% of the world’s fresh water.”

So I guess we’ll keep (A), and hope that the other four answer choices have problems.


I’m not sure that anything is WRONG with (B), but there are three or four things that are spectacularly crappy about (B). (Craptacular? That’s not a word, but it should be.)

For starters, “with 20% of the world’s fresh water” is a lousy way to modify “Siberia’s Lake Baikal.” The preposition “with” generally suggests accompaniment of some sort (“I eat burritos with green chile” or “I went to the movies with my daughter”), and I can’t understand why we would use “with” in this context. Plus, it’s a long way from the thing it modifies. Again, I can’t prove that it’s WRONG, but it’s not great.

I also can’t make sense of the middle modifier, “that is more than all the North American Great Lakes combined.” For starters, I can’t figure out why we’re using a modifier beginning with “that” immediately after a comma. More importantly, the comparison doesn’t work: it’s basically saying that 20% of the world’s fresh water is more than the Great Lakes. You could say that the amount of water in Lake Baikal is greater than the amount of water in the Great Lakes, but it isn’t awesome to say that the amount of water is greater than the lakes themselves.

Finally, there’s no reason to write “…Lake Baikal has more than 300 rivers that drain into it” when we could use a more active construction (“more than 300 rivers drain into Lake Baikal”). The version in (B) isn’t WRONG, exactly, but it’s pretty craptacular compared to (A).

So we can ditch (B).


The most straightforward problem with (B) is that the subject is basically repeated twice: “Siberia’s Lake Baikal, (blah blah modifier), it holds…” That’s definitely not cool.

For bonus points, the modifier beginning with “with” still doesn’t seem quite right (see the explanation to (B) for more on that issue), and the comparison isn’t quite right, either: “Lake Baikal… holds more of the world’s fresh water than all that of the… Great Lakes…” “That” presumably refers to water, so that gives us “Lake Baikal… holds more of the world’s fresh water than [all the water of] the… Great Lakes.” And that’s wildly unnecessary: it’s better just to say that Lake Baikal holds more water than the Great Lakes.

But even if you ignore that last paragraph, the “Lake Baikal… it holds…” thing is a huge problem. So (C) is out.


The “which” jumps out at me first. The phrase “which is more than… the Great Lakes…” seems to modify “20% of the world’s fresh water”, and that doesn’t quite work: it’s illogical to say that a quantity of water is “more than… the Great Lakes.” It might be more than the water in the Great Lakes, but not “more than” the Great Lakes themselves.

Plus, “while” is essentially a synonym for “although” in this case, and that doesn’t make sense: “[Although] more than 300 rivers drain into it, Siberia’s Lake Baikal…[is large].” “Although” suggests some sort of contrast, and there’s definitely no contrast between those two phrases.

So (D) is out.


That opening modifier, “more than all the… Great Lakes combined”, still isn’t great: it’s literally suggesting that Lake Baikal is “more than the Great Lakes”, and that doesn’t make sense. Maybe the amount of water in Lake Baikal is more than the amount in all of the Great Lakes, but Lake Baikal itself isn’t “more than” the Great Lakes.

I’m also not crazy about the use of “with” as a modifier in (E). For more on this issue, see the explanation for (B) above.

(E) isn’t a complete disaster, but (A) does a better job of conveying the meaning of the sentence, so (A) is our answer.

GMATNinja egmat KarishmaB AndrewN

Isn't in A the comparison incorrect where we are comparing water in lake Baikal with the North American Great Lakes combined
It should have been
water in lake Baikal with the water North American Great Lakes combined

GMATNinja egmat KarishmaB AndrewN

Isn't in A the comparison incorrect where we are comparing water in lake Baikal with the North American Great Lakes combined
It should have been
water in lake Baikal with the water North American Great Lakes combined

Isn't in A the comparison incorrect where we are comparing water in lake Baikal with the North American Great Lakes combined
It should have been
water in lake Baikal with the water North American Great Lakes combined

I don't have a clear idea how can we compare sentences that are completely underlines, what to look for in them, and how to answer this one?

A) More than 300 rivers drain into Siberia's Lake Baikal, which holds 20 percent of the world's fresh water, more than all the North American Great Lakes combined.

GMATNinja MartyTargetTestPrep



Doesn't this seem to be comparing the world's fresh water to all the North American Great Lakes combined? As in, it's comparing fresh water and lakes, while it should actually be comparing fresh water, and the water in all the North American Great lakes combined?