[单项选择]

An important businessman was asked to give a twenty-minute speech in another city. He was too busy to write it himself, so he asked his secretary to put one together for him out of a large book of speeches which she had on her desk. She typed one out for him, and he picked it up just in time to rush off to his plane. But when he gave his speech, it ran on for an hour, and the audience (听众) was getting very tired of it by the end.
When the businessman got back to his office, he said to his secretary, "I told you it should be a twenty-minute speech!"
"That’s what I gave you," she answered, "the original and two copies. The original for you to read at the meeting, and two copies for the files, after you have checked them."

Why was the businessman not satisfied with his secretary（）
A. He had given the same speech three times.
B. His speech lasted for an hour.
C. He had made three speeches.
D. The speech was not well written.