Answer:
A. Mr. Bixby asks, “Didn’t you know there was no bottom in that crossing?”
Step-by-step explanation:
"Cub Pilot" is from Mark wain's "Life On The Mississippi" where Samuel Clemens/ Mark Twain got to work as a 'junior' pilot. This book details his life as a seafaring man and the hard lessons he learned under his chief Mr. Bixby.
Mr. Bixby wanted to test the "young cub" of his abilities to navigate under pressure. So, he told Mark he's going "below awhile", leaving the orders to run the boat to him. When asked if he can navigate without his help, Mark confidently told him he could, "with [his] eyes shut" for he knows he couldn't hit the bottom of the river "with a church steeple". Such was his knowledge of the course and confidence but when Mr. Bixby simply asked "You think so, do you?", all the confidence in him went away. He lost his composure and his mind began playing with him. Even though he knows the route like the back of his hand, that question lingered in his mind so much that he began to question everything.
After the "test", Mr. Bixby asked Mark "Didn't you know there was no bottom in that crossing?" after he (Mark) was left embarrassed and lack confidence in himself. This question reveals that if you believe in and trust yourself, then there is nothing that can shake your confidence. Thus, the correct answer is option A.