Correct the punctuation in this​ sentence:
​"The Beatles are still my favorite​ band, Charles​ said."
A.
​"The Beatles are still my favorite band. Charles​ said."
B.
The Beatles are still my favorite​ band, Charles said.
C.
​"The Beatles are still my favorite​ band," Charles said.
D.
​"The Beatles are still my favorite​ band, Charles said.