Question

id: e818241b astronomers are confident that the star betelgeuse will eventually consume all the helium in its core and explode in a supernova. they are much less confident, however, about when this will happen, since that depends on internal characteristics of betelgeuse that are largely unknown. astrophysicist sarafina el - badry nance and colleagues recently investigated whether acoustic waves in the star could be used to determine internal stellar states but concluded that this method could not sufficiently reveal betelgeuse’s internal characteristics to allow its evolutionary state to be firmly fixed. which choice best describes the function of the second sentence in the overall structure of the text? a. it describes a serious limitation of the method used by nance and colleagues. b. it presents the central finding reported by nance and colleagues. c. it identifies the problem that nance and colleagues attempted to solve but did not. d. it explains how the work of nance and colleagues was received by others in the field.

Explanation:

The first sentence states that astronomers are unsure about when Betelgeuse will explode due to unknown internal characteristics. The second - sentence then mentions that Nance and colleagues investigated a method to determine internal stellar states but found it insufficient. So, the second sentence identifies the problem (determining internal characteristics to fix the evolutionary state) that Nance and colleagues tried to solve but couldn't.

Answer:

C. It identifies the problem that Nance and colleagues attempted to solve but did not.