Jamboree Question of the Day - Day 30, Dec 8th 2010

After adopting broadband internet access, wireless personal digital assistants, and super-fast home PCs, Weston Insurance has hired new employees, which doubles to 250 the junior staff in the claims department working from home.

(A) which doubles to 250 the junior staff in the claims department

(B) doubling to 250 the number of junior staff members in the claims department

(C) which doubles to 250 the junior staff of the claims department

(D) doubling to 250 the number of junior staff members of the claims department

(E) which doubles to 250 the junior staff in the claims department that 

Solution (Posted on Dec 9th):

The best answer is B. The pronoun which should be used to refer to a previously mentioned noun, not to the idea expressed in an entire clause. In A, C, and E there is no specific noun.