Which is the correct way to punctuate the sentence below?

Question

When did the California Gold Rush begin? asked Mrs. Sampson.
A.
When did the California Gold Rush begin? "asked Mrs. Sampson."

B.
"When did the California Gold Rush begin?" asked Mrs. Sampson.

C.
"When did the California Gold Rush begin? asked Mrs. Sampson."

D.
When did the "California Gold Rush begin?" asked Mrs. Sampson.

Answer 1

B.
"When did the California Gold Rush begin?" asked Mrs. Sampson.