A. The president can veto legislation.
A check on the power of the legislative branch means that the legislative branch is the one being stopped. There can be two ways that a bill that is passed by the legislative branch can be stopped:
1) A veto against the bill (Option A)
2) The Supreme Court rules that the law is unconstitutional.
Note that for option (C), while it states the Supreme Court, it is talking about presidential actions (executive branch powers), and so it is not the answer
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