He was said to own a thousand slaves, and I think this estimate quite within the truth.

Question

A. The comma is used to separate coordinate adjectives.
B. The comma is used after an introductory word, phrase, or clause.
C. The comma is used to separate three or more words, phrases, or clauses in a series.
D. The comma is used before a conjunction that joins independent clauses in a compound sentence.

Answer 1

B. The comma is used after an introductory word, phrase, or clause.