Correct option is B
Given
Statement :
If you are an efficient typist, then we definitely have a job for you.
Conclusions:
I. You are an efficient typist - Does not follow (The statement does not confirm that the person is an efficient typist).
II. We are in need of an efficient typist - Follow (The statement clearly implies that there is a job available for an efficient typist, which means the company is looking for one).
So, Only conclusion II follows.
Thus, the correct option is: (b)