"the clothing drive was going better than planned."
what kind of sentence is this?
a. complex sentence
b. simple sentence
c. compound-complex sentence
d. compound sentence

The prefix that changes the meaning of bacterial from "relating to or caused by bacteria" to "preventing bacteria" is anti-

The prefix anti means “against,” “opposite of,” “antiparticle of,” used in the formation of compound words ( anticline ); used freely in combination with elements of any origin ( antibody; antifreeze; antiknock; antilepton ).

Prefixes are letters which added to the beginning of a word in order to make a new word with a different meaning. Prefixes can, for instance, create a new word opposite in meaning to the word the prefix is attached to.