English grammar – Spot the error (choose the part with an error or “No error”). Sentence: The book is making / waves and the sale / is quite brisk in / all major cities.

Introduction / Context:
Here the test is subject–verb number agreement in a coordinated clause that refers to commerce. Common idiom is “sales are brisk.” If we retain “the sale” as a mass/collective noun, the more natural correction is still to use the plural “sales” and match the verb accordingly.

Given Data / Assumptions:

• Clause 1: “The book is making waves …” is fine.
• Clause 2 introduces “the sale …” followed by the verb “is.”
• In business English, the plural “sales” takes a plural verb.

Concept / Approach:
Correct the number of the predicate: “sales are brisk.” Exams typically mark the verb segment as the error because agreement must reflect the (intended) plural subject “sales.”

Step-by-Step Solution:

Verification / Alternative check:

Why Other Options Are Wrong:

Common Pitfalls:

Final Answer:
is quite brisk in