Which of these excerpts from Mark Twain's Life on the Mississippi best shows Twain's subtle sense of humor?

A. The captain lifts his hand, a bell rings, the wheels stop; then they turn back, churning the water to foam, and the steamer is at rest.

B. The great Mississippi, the majestic, the magnificent Mississippirolling its mile-wide tide along, shining in the sun

C. The minister's son became an engineer. The doctor's and the postmaster's sons became "mud clerks."

D. Now and then we had a hope that if we lived and were good, God would permit us to be pirates.

D. Now and then we had a hope that if we lived and were good, God would permit us to be pirates.

This excerpt best shows Mark Twain's subtle sense of humor as it playfully juxtaposes the moral expectation of being good with the childhood fantasy of becoming pirates, which are traditionally seen as immoral and unruly characters. The humor lies in the irony of hoping that good behavior would be rewarded with a life of piracy.