It is theoretically possible that bacteria developed on Mars early in its history and that some were carried to Earth by a meteorite. However, strains of bacteria from different planets would probably have substantial differences in protein structure that would persist over time, and no two bacterial strains on Earth are different enough to have arisen on different planets. So, even if bacteria did arrive on Earth from Mars, they must have died out.
The argument is most vulnerable to which of the following criticisms?
(A) It fails to establish whether bacteria actually developed on Mars
(B) it fails to establish how likely it is that Martian bacteria were transported to Earth
(C) It fails to consider whether there were means other than meteorites by which Martian bacteria could have been carried to Earth.
(D) It fails to consider whether all bacteria now on Earth could have arisen from transported Martian bacteria.
(E) It fails to consider whether there could have been strains of bacteria that originated on Earth and later died out.Note: There are two questions available with the similar stimulus and same first line but different question. The other question (complete the passage) is discussed in: it-is-theoretically-possible-that-bacteria-developed-on-q2-46449.html
Whats wrong with D and E...
Can someone explain...?
This is one of the most twister questions I have seen on GMAT. But not because of logic but sentence construction. I would have been scratching for long in understanding the meaning. Lets deconstruct.Fact 1:
It is theoretically possible that bacteria developed on Mars early in its history and that some were carried to Earth by a meteorite. Fact 2:
However, strains of bacteria from different planets would probably have substantial differences in protein structure that would persist over time, and
Not of much significanceFact3:
no two bacterial strains on Earth are different enough to have arisen on different planets.
It looked like an SC question to me for first 20 times I looked at it. But, guess GMAT is all about persistence
Let us first remove this "no" from beginning to understand the meaning: "two bacterial strains on Earth are different"
Now place "not" after "are": "two bacterial strains on Earth are not
So, this sentence basically says that bacterial strains on earth are so same that they must be of only one origin.Conclusion:
So, even if bacteria did arrive on Earth from Mars, they must have died out.
Bacteria from Mars, if on earth, must have died out.Summary:
We can have only one source for all bacteria on earth. So all bacteria from Mars, if reached earth, would have died out on earth.
What will weaken this? Bacteria from Mars didn't die.
D says exactly that.
E says that earth bacteria died out. It is extra information but doesnt deal with Martian bacteria(which is part of conclusion)
Correct me if this line of thinking looks wrong..
If you know what you're worth, then go out and get what you're worth. But you gotta be willing to take the hits, and not pointing fingers saying you ain't where you wanna be because of anybody! Cowards do that and You're better than that!
The path is long, but self-surrender makes it short; the way is difficult, but perfect trust makes it easy.
Fire the final bullet only when you are constantly hitting the Bull's eye, till then KEEP PRACTICING.
Failure establishes only this, that our determination to succeed was not strong enough.
Getting defeated is just a temporary notion, giving it up is what makes it permanent.
Press +1 Kudos, if you think my post gave u a tiny tip.