Fill in the blank using the appropriate verb form:
Can you wait for me? It _________ very long.
a. Won’t be
b. Haven’t be
c. Arent’t be
d. Didn’t be

Hint: The action’s scope is expected to continue for some time in the future.

Complete answer:
The Future Tense denotes those actions that may take place in the future. To conjugate verbs in the future tense, you must add the modal verb- will/shall and the respective auxiliary verb. After doing this, you must conjugate the infinitive as per the given type of tense. ‘Infinitive’ refers to the ‘to form’ of a verb. E.g. - to eat.
There are four types of future tenses:
The Simple Future Tense is used when an action is indefinite in the future. It doesn’t make use of any auxiliary verb.
The Future Continuous Tense is used when an action is continuous in the future. The infinitive form of such verbs is preceded by the auxiliary be.
The Future Perfect Tense is used when an action has been completed in the future. The infinitive form of such verbs is preceded by the auxiliary have.
The Future Perfect Continuous Tense is used when an action is expected to continue up until a point in the future. The infinitive form of such verbs is preceded by the auxiliary have been.

In the above question, the action isn’t indefinite in the future. Nor do we know when exactly it will end. All we know is that it is expected to continue for some time in the future. This means that the tense of the action is the Future Continuous Tense or the Future Progressive Tense. Following the rules of conjugation, the correct answer is option ‘a’ won’t be.

Note: To avoid making errors, consider when the action will start and end in the future.