Answer: B) Timothy worked till late, as it was the best time to think.
Explanation: an adjective is a word that describes or modify a noun. An infinitive phrase is a group of words that uses an infinitive (“to” + verb). It can work like a noun, adjective, or adverb in a sentence. From the given options, the sentence that has an infinitive phrase acting as an adjective is the corresponding to option B, where the infinitive phrase "to think" is modifying the noun "time."
