[单项选择]

A doctor was once teaching a (1) of medical students at a famous university in Edinburgh. An injured man was (2) in, and the doctor turned to (3) of the students and asked him, "What’s (4) with this man"
"I don’t know, sir," the students answered. "Shall I examine him and (5) out" "There is no (6) to examine him," said the doctor.
"You (7) know without asking questions. He had (8) his right knee. Don’t you notice the (9) he walked He hurt it by (10) it in the fire. You see his trouser leg is burnt away at the (11) . This is Monday morning. Yesterday was (12) , but on Saturday the roads were (13) and muddy. The man’s trousers are muddy all over. The man fell down on Saturday (14) . "
The doctor then turned to the man and said, "You (15) your wages on Saturday and went to a pub
A. part
B. class
C. pair
D. few