Select the most appropriate option to fill in the blank. Raj is an ______…

Concept

When a blank falls between an article ('a'/'an') and a noun, the word that fills it must be an adjective, because the article + adjective + noun sequence is the standard pattern in English for describing a noun. The chosen word must also carry the part of speech required by that sentence position, not merely resemble a fitting word.

Application

In 'Raj is an ______ student,' the word 'student' is a noun preceded by the article 'an', so the blank needs an adjective that can meaningfully describe a student. Among the options, 'intelligent' is an adjective, and it correctly occupies the article + ___ + noun position while also supplying a sensible descriptive quality for a student.

Contrast

• 'intelligible' — an adjective, but it means able to be understood or comprehended (used for speech, writing, or an explanation), not a quality describing a person's mental ability.

• 'intelligence' — a noun. English does allow a noun to modify another noun attributively in some fixed collocations (e.g. 'an engineering student'), but 'intelligence' is not conventionally used to modify 'student' this way; it names an abstract quality rather than functioning as a descriptive modifier, so it cannot fill the adjective slot the sentence needs.

• 'intelligently' — an adverb, so it modifies verbs, not nouns, and therefore cannot occupy the adjective slot before 'student'.

Reading the completed sentence back — 'Raj is an intelligent student' — confirms it is grammatically well-formed (article + adjective + noun) and semantically coherent, while each of the other options fails on either grammar or meaning.