13. The students must have obeyed
their teachers.

a)Their teachers might have obeyed by
the students.
O
2)Their teachers might have been
obeyed by the students.
O
3)Their teachers must have been obeyed
by the students.
O
4)Their teachers must have obeyed by
the students.​

Respuesta :

Answer:

The answer is 3

Explanation:

A is automatically out ruled because "might" contradicts the "must" in the sentence above.

2 Also contradicts the "must" in the sentence above.

3 Does not contradict the "must" and makes grammatical sense. Therefore, 3 is the answer

4 Doesn't contradict the *must" but does not make grammatical sense.