Correct option is B
Correct Answer: B
Explanation:
· (A) “Bloated valuation of stocks as a result” — correct phrase.
· (B) “of ultra-low interest rates are one” — error.
Error Rule:
The subject is “valuation” (singular), so the verb must also be singular.
Incorrect: are one
Correct: is one
· (C) Correct — no issue.
· (D) Correct — parallel structure maintained.
Conclusion:
Error lies in part B due to subject-verb agreement (singular subject requires singular verb).