Correct Answer: Madam Hooch said to the students, "What are you waiting for?"

Solution : The correct choice is the fourth option.

Direct speech, where the focus is on the speaker or the person directly expressing the words.

The steps of conversion are as follows:

• The reporting verb "asked" is changed to "said".
• The reported clause will start with the question word "what" to emphasise the interrogative nature of the sentence.
• The third-person pronoun "they" is changed to the second-person pronoun "you".
• The past continuous tense "were waiting" is changed to the present continuous tense "are waiting".
• The words of the speaker are enclosed in the inverted commas.

Therefore, the direct speech would be: Madam Hooch said to the students, "What are you waiting for?"