Question 10: The new secretary will take up her post in May.
The correct answer is C. "take up" means to start or begin a new job or responsibility.

Question 11: Mike behaved like an adult. I think he is more mature than the other boys at his class.
The correct answer is B. "mature" means having or showing the mental and emotional qualities of an adult, so it fits the context given.

10   . C
11    . B

10. C, take up
11. A. intelligent