"He answered the question correctly."

The correct answer is Option (4) → Adverb of Manner

An adverb is a word that tells how, when, where or how much something happens. It can also describe an adjective or another adverb, for example she sings sweetly, very hot.

Correctly means in the right way. It tells how he answered the question.

Option	What it tells	Example
(1) Adverb of Reason	why something happens (therefore, hence)	He was ill and hence missed the class.
(2) Adverb of Time	when something happens	I met my cousin yesterday.
(3) Adverb of Place	where something happens (here, there, outside)	Please wait here for a minute.
(4) Adverb of Manner (answer)	how an action is done	Anil spelt every word correctly in the test.