Question #N916

The sentence "The best way to help your community is to donate to charities, volunteering at local food banks, or to assist seniors with transportation." contains a grammatical error.

Which revision of the sentence corrects the grammatical error?
A. The best way to help your community is to donate to charities, to volunteer at local food banks, or to assist seniors with transportation.
B. The best way to help your community is to donate to charities, volunteering at local food banks, or assist seniors with transportation.
C. The best way to help your community is to donate to charities, volunteer at local food banks, and assist seniors with transportation.
D. The best way to help your community is to donate to charities, volunteering at local food banks, or to assist seniors with transportation.