The Sports Medicine Programs of the Olympic Training Center, a complex where final try outs are held for athletes representing the US in the Olympics, is geared toward enhancing athletes' performance and toward their preparation for international competition.
A.) is geared toward enhancing athletes' performance and toward their preparation
B.) is geared to enhance the performance of athletes and to prepare them
C.) are geared to enhance athletes performance and their preparation
D.) are geared toward the enhancement of athletes' performance and toward preparing them
E.) are geared toward enhancing the performance of athletes and preparing them

I agree with the OA. However, I noticed something new to me: Why doesn't the choice E (the OA) repeat "toward" in the second element (preparing)? Based on my knowledge about parallelism, it should be "...and TOWARD preparing them."
I know that it is not necessary to repeat certain words in parallel structures. For instance: I like TO play drums, ride my mountain bike, and paint heavy metal pictures. (It's true!). As you can see, it is not necessary to repeat "to". I want to know whether is the same case when we use prepositions. My MGMAT SC book only talks about verbs, not prepositions.

Please, your help.