Correct Answer: can

Solution : The correct answer is option 1.

I always told him not to postpone until tomorrow what he can do today.

Explanation:

Can is a modal verb.

The ability, possibility, and probability of a subject performing an action are represented by modal verbs, which are helping verbs that are used in conjunction with the main verb to emphasize the necessity of an action. You can use modal verbs to make requests, suggestions, and offers.

Modal verbs can be used to express the possibility or potential for an action to occur.

Can is used to indicate whether a subject has the capacity to act or to ask for permission to act