"She frequently visits her grandparents."

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

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.

The adverb in this sentence is frequently. It means often, or many times. She visits her grandparents many times.

Option	What it tells	Example
(1) Adverb of Reason	why something happens	He was ill and hence missed the class.
(2) Adverb of Time	when (today, soon, later): “frequently” tells how many times, not when	We will leave for the station soon.
(3) Adverb of Place	where something happens	Please wait outside the room.
(4) Adverb of Frequency (answer)	answers the question how often? (always, often, sometimes, never)	Meena frequently forgets her lunch box at home.