Sentence Correction

Among lower- paid workers, union members are less likely than non union members to be enrolled in lower- end insurance plans imposing stricter limits on medical services and requiring doctors to see more patients, and spend less time with each

a). imposing stricter limits on medical services and requiring doctors to see more patients, and spend
b). imposing stricter limits on medical services , requiring doctors to see more patients, and spending
c). that impose stricter limits on medical services, require doctors to see more patients, and spend
d). that impose stricter limits on medical services and require doctors to see more patients, and spending
e). that impose stricter limits on medical services, requiring doctors to see more patients and spending

I am confused with A and D. I am not finding how to eliminate choices between A and D.

A is maintaining parallel construction between imposing and requiring but fail to maintain parallel construction between to see and spend. D is maintaining parallel construction between impose and require but fail to maintain parallel construction between to see and spending. Can anyone please let me know where i am wrong and how to eliminate one of them.

Thanks a lot in advance.