reported speech เราเปลี่ยน tense จาก present to past เพราะ have to เป็น verb 1 ต้องเปลี่ยนเป็น verb 2 คือ had to และอีกอย่างคือ What ซึ่งเป็น question words ใช้เป็นตัวเชื่อม ดังนั้น ข้อ 3 คือคำตอบ
Reported speech tense from past to present, we changed it to have the verb 1 to change a verb 2 is What is had to, and that is the question words used as a link, so the answer is 3.
reported speech, we changed from present to past tense verb 1 I have to be to change the verb 2 What is had to, and the other is the question words used as a link, so 3 is the answer.
Reported speech we change tense from present to past because have to is verb 1 to change is the verb 2 is had to and another is... What which is used as a question words welding, so the 3 is the answer.