Question

the pronoun in bold is not vague. select its one clear antecedent. scientists have discovered that mercury is shrinking! in the process, its surface is wrinkling and cracking.

Explanation:

An antecedent is the word, phrase or clause that a pronoun refers to. In the sentence "The pronoun in bold is not vague. Scientists have discovered that Mercury is shrinking! In the process, its surface is wrinkling and cracking.", the pronoun "its" refers to Mercury.

Answer:

Mercury