Select the most appropriate word to fill in the blank.
When I first met my neighbours I took an ______ liking to them.

Options

A. instant
B. instantly
C. instance
D. instantaneously

Explanation

instant(n)- A very short period of time. Instantly- adverb of instant. Instance-an example or case. Instantaneously- adverb Since we need a noun after article An so option (a) fits to the context of the sentence.