Question

How does adding the affix -etic to the words energy, athlete, and poet change the meanings of these words?

It changes them from nouns to adjectives.
It changes them from adjectives to nouns.
It changes them from nouns to adverbs.
It changes them from adverbs to nouns.

Answer 1

It changes them from nouns to adjectives.

Adding -etic (or -ic in the case of poet → poetic) forms adjectives: energy → energetic, athlete → athletic, poet → poetic (e.g., "an energetic runner," "an athletic player," "a poetic line").