请教吖！GWD1-Q7~

GWD1-Q7:

A recent review of pay scales indicates that CEO’s now earn an average of 419 times more pay than blue-collar workers, compared to a ratio of 42 times in 1980.

1. that CEO’s now earn an average of 419 times more pay than blue-collar workers, compared to a ratio of 42 times

2. that, on average, CEO’s now earn 419 times the pay of blue-collar workers, a ratio that compares to 42 times

Ｃ、that, on average, CEO’s now earn 419 times the pay of blue-collar workers, as compared to 42 times their pay, the ratio

Ｅ、CEO’s now earning an average of 419 times the pay of blue-collar workers, compared to the ratio of 42 times'

答案是选Ｃ、CEO's now earn ~~　为什么不用CEO's now earning ~~??