The latest review of pay scales in a particular

[Vincen]

The latest review of pay scales in a particular company shows that g officers get paid an average of 1.8 times more salary than product development engineers, compared to a ratio of 1.3 times ten years ago.

(A) that marketing officers get paid an average of 1.8 times more salary than product development engineers, compared to a ratio of 1.3 times

(B) marketing officers who get paid on average 1.8 times more salary than product development engineers, as compared to 1.3 times their salary, the ratio

(C) that, on average, marketing officers get paid 1.8 times the salary of product development engineers, as compared to 1.3 times their salary, the ratio

(D) marketing officers now having an average of 1.8 times the salary of a product development engineers, compared to the ratio of 1.3 times

(E) that, on average, marketing officers get paid 1.8 times the salary of product development engineers, a ratio that compares to 1.3 times

The OA is C.

Can any expert clarify this question to me. I don't know how can I solve it.