Final answer:
The correct answer to the question is 'd) Clarity,' as the proverbial phrase is 'brevity is the soul of wit,' indicating that concise and clear expression is valued.
Step-by-step explanation:
Proverbially, "brevity is the soul of wit," which means that being concise is a sign of intelligence and humor. Therefore, the correct answer to the question is d) Clarity. The statement suggests that a clear and concise expression is the essence of being witty and insightful. This proverbial wisdom aligns with advice on writing and speaking, where clarity and succinctness are often prized above verbosity.