What would be the best option to complete the passage? It

[BTGmoderatorDC]

What would be the best option to complete the passage?

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 ________.


(A) Whether or not bacteria actually developed on Mars.

(B) Its likely it is that Martian bacteria were transported from Earth.

(C) Martian bacteria could have been carried to Earth by means other than meteorites.

(D) All bacteria now on Earth could have arisen from transported Martian bacteria.

(E) There could have been strains of bacteria that originated on Earth and later died out.

OA D

Source: GMAT Prep

[deloitte247]

OPTION A - INCORRECT
Whether or not bacteria actually developed in mars is not the main concern of the argument, so it cannot best complete the passage.

OPTION B - INCORRECT
This cannot best complete the passage because the bacteria being talked is from mars and not from earth.

OPTION C - INCORRECT
The passage is concerned with bacteria that were carried to earth through meteorite, any other means of carriage is outside the scope of the argument.

OPTION D - CORRECT
It is very much possible that all bacteria on earth could have been transported from mars since no two bacteria on earth are different enough to have arisen from different planets. It means that all bacteria are from the same planet.

OPTION E - INCORRECT
There's no evidence or indication to back this up in the passage.