Reading Comprehension

og-15 RC-3

Jupiter's gravity attracts comets and asteroids
passing near it, substantially increasing the
bombardment rate of the inner moons compared to
that of the outer ones. But because of Io's high
degree of geological activity, its surface undergoes
more-or-less continuous volcanic resurfacing.






The author's reference to Jupiter's gravity in line 25
serves primarily to
(A) indicate why the absence of craters on Io's
surface is surprising
(B) explain the presence of craters on the surface
of Jupiter's four largest moons
(C) provide an explanation for the lack of geological
activity on Callisto
(D) contrast Jupiter's characteristics with the
characteristics of its four largest moons
(E) illustrate the similarity between Jupiter's four
largest moons and the planets of the solar
system


Why option B is wrong? The portion highlighted in bold in above passage suggests that gravity is responsible for both inner and outer moons. Although the rate is different.

Can anyone please help me.


Thanks & Regards,
Vishal

This is a Function question, so it is not concerned with what the passage says. The phrase "serves primarily to" tells us the question is asking what ROLE this specific detail plays in the structure of the passage. Don't confuse it with a Detail question.

Rephrase: WHY did the author mention J's gravity?

Well, ask yourself, what paragraph is line 25 found in? What did you decide what the function of that paragraph? Is it information or persuasive?

WHY does the author mention the fact of J's gravity? Its point is that J's gravity means its moons get smashed with asteroids.

Notice the next sentence, "But because of Io's..." The word "but" indicates a contrasting idea. Io is one of Jupiter's moons. So this contrasting idea is probably that, even though J's moons get smashed with asteroids, Io is somehow special and doesn't get smashed up.

Prediction: to show that Io is not like J's other moons

The correct answer is A.

To get this type of question correct, you must get inside the head of the author.