select the most appropriate word to fill in the blank. The doctor often made his patients ______ for long. (a) to wait (b) wait (c) waiting (d) waited

Options

A. to wait
B. wait
C. waiting
D. waited

Explanation

Made is a causative verb which is used to indicate that one person causes another person to do something for the first person. Whereas, “Made + Object + Bare Infinitive(without the preposition ’to’)” is the correct structure of the sentence using ‘made’. Hence, ‘made his patients(object) wait’ will be the most appropriate answer.