Floating in the waters of the equatorial Pacific, an
array of buoys collects and transmits data on long-term
interactions between the ocean and the /u atmosphere, interactions that affect /u global climate.

a atmosphere, interactions that affect
b atmosphere, with interactions affecting
c atmosphere that affects
d atmosphere that is affecting
e atmosphere as affects

correct ans is: A

however, I picked C without knowing exactly why (more of a sounds good guess). I have read the explanation in the Verbal Review, but I still do not understand why A is best here,

could someone please explain more?

thanks