SAT question 7a1877be (Command Of Evidence)

Question

Employing high-performance liquid chromatography—a process that uses pressurized water to separate material into its component molecules—astrochemist Yashiro Oba and colleagues analyzed two samples of the Murchison meteorite that landed in Australia as well as soil from the landing zone of the meteorite to determine the concentrations of various organic molecules. By comparing the relative concentrations of types of molecules known as nucleobases in the Murchison meteorite with those in the soil, the team concluded that there is evidence that the nucleobases in the Murchison meteorite formed in space and are not the result of contamination on Earth. Which choice best describes data from the table that support the team's conclusion?

College Board · Accepted Answer

The correct answer is A. Choice A is the best answer. The researchers concluded that the meteorite's nucleobases weren't the result of soil contamination. Presence of nucleobases in the meteorite and not in soil provides evidence that those nucleobases likely didn't come from the soil.

Nucleobase Concentrations from Murchison Meteorite and Soil Samples in Parts per Billion
Nucleobase	Murchison meteorite sample 1	Murchison meteorite sample 2	Murchison soil sample
Isoguanine	$0.5$	$0.04$	not detected
Purine	$0.2$	$0.02$	not detected
Xanthine	$39$	$3$	$1$
Adenine	$15$	$1$	$40$
Hypoxanthine	$24$	$1$	$2$

Explanation

Why the other choices are wrong

SAT Question 7a1877be: Command Of Evidence answer and explanation

Explanation

Why the other choices are wrong