PERT Practice Test 2026 – Comprehensive Study Guide for Postsecondary Education Readiness Success!

The choice "explains" is correct because it provides the subject-verb agreement needed in the sentence. The phrase “Chapter 12” is singular, referring to one specific chapter. Thus, it requires a singular verb form "explains" to maintain grammatical consistency.

In contrast, the other options do not align correctly with the singular subject. "They explain" incorrectly uses "they," which implies a plural subject, misrepresenting the focus on just one chapter. "They will explain" also implies a future tense with a plural subject, which does not fit the context since the sentence is likely addressing a specific explanation that is currently relevant. "No change" would mean retaining a potential error, as the original form does not guarantee proper agreement.