7175. He had to curtail his leave as a lot of work was pending in his office.

✅ The correct answer is option C.
Cancel : decide or announce that (a planned event) will not take place.

Extend : cause to cover a wider area; make larger.

Shorten : make or become shorter.

Postpone : cause or arrange for (something) to take place at a time later than that first scheduled.

Curtail : reduce in extent or quantity; impose a restriction on.

Synonym of Curtail is Shorten