Senators can use a filibuster in order to:

a. prevent the Senate from voting on a bill

b. add amendments to a bill they dislike

c. override a presidential veto on a bill

d. force a committee to approve a bill

A. prevent the Senate from voting on a bill

Explanation:

The filibuster is a political tactic or procedure employed by members of the Congress, especially by Senators, in which one or more members intentionally give long and often irrelevant speeches to debate a proposed piece of legislation, in order to delay or prevent the chamber from voting on a bill. However, when this happens, a senator may invoke cloture, which it's their only defense to bring the debate to a quick end.