Answer - A
Explanation
"Must" is used in situations where the action is a requirement, or where the action can be predicted with much accuracy.
Answer - C
Explanation
"Could" is used to speak on the ability of the doer in the past time.
Q 3 − The company … close down if the loans are not paid soon.
Answer - D
Explanation
"Will" is used to talk about an action happening in the future.
Answer - D
Explanation
"Shall I" is a question form used to offer help politely, instead of the informal "Let me ..." or "allow me to ...".
Q 5 − If I can’t find it here, then I … have left my medicine in the car.
Answer - D
Explanation
"Must" is used in situations where the action is a requirement, or where the action can be predicted with much accuracy.
Q 6 − You … take a raincoat with you. It looks like raining.
Answer - D
Explanation
"Ought to, should" are used to suggest actions, provide opinions and give advice.
Q 7 − You don’t … do what he says just because he says so.
Answer - B
Explanation
"Don't/didn't/doesn't have to" is used in situations where the action wasn't mandatory to do.
Q 8 − Lindsay watched the movie in French, though she … understand much.
Answer - C
Explanation
"Could" is used to speak on the ability of the doer in the past time. Similarly, "Could not" is used to speak about the disability of someone in doing an action in the present or future.
Answer - B
Explanation
"Could I" is a question form used to ask permission.
Answer - A
Explanation
"Ought to, should" are used to suggest actions, provide opinions and give advice.