请仔细阅读Mr. Smith对Sam说的话，从A、B、C、D中找出可以替换1—4小题中划线部分的选项, 并完成第5小题。

A. be more patient         B. be yourself C. understand             D. no chance

“Sam, you’re usually so outgoing and friendly. Don’t be afraid to show your true colors.”
“If you get the picture. Please do it again.” Mr. Smith.
“Keep your shirt on and don’t be nervous. They’ll be here before the class starts.”
“Sam, don’t be so confident. We will have a fat chance to pass the test.”
What’s the relationship between Mr. Smith and Sam?

A．Father and son.	B．Doctor and patient.
C．Teacher and student.	D．Driver and passenger.