Antibiotic Derived from Penicillin: Understanding 'Derivative' in Science

The correct answer is:

a. derivative

The sentence should be: 'The new antibiotic is listed as a derivative of penicillin because it was produced from a penicillin base.'

A 'derivative' is a word that describes something that is based on or derived from something else. In this sentence, the new antibiotic is derived from a penicillin base, so it is considered a derivative of penicillin.