In 1871, Charles Darwin published The Descent of Man, and before that,

Hello Mike ,

Original Sentence says principles of genetics was discovered using pea plant experiments
whereas B says during the pea plant experiments ; doesnt this alter the meaning of the sentence ??

Dear rohitkumar77,
I'm happy to respond.

Think about what a scientific experiment is. The scientist has a question about something currently unknown, then she sets up an experiment to observe what happens on special conditions. A discovery may happen during the actual course of the experiment, "on the spot," or if the data or patterns are complicated, it may take time to process the data before one has a discovery. For practical purposes, both the time in the lab with the experimental design and the time afterwards in one's office processing all that data on a computer could both be called "during the experiment." To draw a distinction between those would be splitting hairs in a way that the GMAT does not do.

By contrast, "using the experiment" is an awkward formulation. In some sense, this is a sloppy colloquial formulation. We get the sense of what the author is trying to say, but technically, what does it mean to "use" an experiment? It's an extremely odd phrasing. Presumably, it means to learn or understand something from the data, and of course this learning happened "during the experiment." It's not really clear what kind of "using" one would do besides this.

Insofar as we can discern the meaning in (A), choice (B) formulates it more clearly.

Does this make sense?
Mike
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this / that can not be used as pronoun refering to an preceding idea on gmat land. this is very easy error. in nytimes online newspaper, this can be used frequently. this usage is wrong on gmat. A and D are gone.
in C. there is no meaning relation for which "although" can be used. no logic, C is gone
in E, before Charles, mendel dad conduct is not logic. the logic meaning is before the action of darwin not before darwin. E gone

Hi Mike,

I have quick question about Choice E.

I saw you analysis for Choice E hut I do not understand why 'before' should be followed by full clause.

In some sentences I saw 'before' + 'participial' such as:

Before eating my dinner, I had finished my assignments.

Can you please help me clarify my misunderstanding?

Thanks in advance

Hi Mike,
IMO In option A 'they' is ambiguous . Please correct If I am wrong .

Yeah, even i think so.
In C, it should be "...had already discovered" since we are talking about two events of the past.
In D and E, "...publishing" doesn't make sense.

Dear anje29 & hotshot02,

I'm the author of this question and I'm happy to respond.

First of all, let's be perfectly clear. Choice (A) in this problem is a complete train wreck. Even with no pronoun mistake, it would be an irredeemable abomination of an answer choice.

Given that, I would say that the "they" is probably ambiguous, at least by GMAT standards. You see, the pronoun-antecedent relationship is complicated, depending on grammar & logic & rhetoric. The grammar question we ask is: what plural nouns precede the pronoun? The two plural-noun candidate are "the principles of genetics" and "famous pea plant experiments." But the first is rhetorically elevated because it is part of the focus of the sentence, whereas the second appears in a parenthetical statement, and thus is deemphasized. These two plural nouns are not symmetrical in their weight. This gives the pronoun "they" more of a link to the first noun. Of course, this is all in a gray area, and in a correct answer on the GMAT, everything about pronoun-antecedent relationship is crystal clear. In real life, the pronoun "they" would probably pass as unambiguous, but it's not up to the GMAT standards.

Two things you should appreciate:
1) There is always a great deal going on, at several different levels, with the pronoun-antecedent relationship. This will help you to appreciate what masterpieces the OAs are on official questions.
2) Even if (A) in this question had no pronoun problem, it would still be very wrong. My advice is to ignore the pronoun problem and focus on everything else that's wrong with (A).

Does all this make sense?
Mike
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dear mikegary
i read your article on past perfect and came to this question through that. As per my understanding of your article, the use of "had" should be incorrect in B as it already uses time marker "by the time" and "1871". For the following reason I chose C. could you please correct my understanding? Thanks.

IMO B.

Since it contains the past perfect tense to show Gregor Mendel discovery had already happened by the time Charles Darwin published his book. Structurally, B is the most appropriate one