Which sentence has unclear pronoun reference?

Why should students write a research question in the prewriting stage of the writing process?

what is the color of the sky

Select the sentence with correct comma placement.

Why are signal phrases important in research writing?

Select the sentence with correct pronoun-antecedent agreement.

 A student wants to reference an organization in an academic paper. Which sentence correctly capitalizes the organization’s name?

Match each grammar concept on the left with its correct definition or example on the right.

Identify the misplaced modifier in the sentence:”He bought a book for his sister that explained scientific theories.

How can the following fragment be corrected? “While studying for the exam.”