Question

the role of the senate in regard to treaties is to
approve international treaties.
advise during negotiations.
have the president of the senate sign the treaty.
negotiate the terms and conditions of the treaty.

Explanation:

The U.S. Constitution (Article II, Section 2) gives the President the power to make treaties, but they must be ratified by the Senate. A two - thirds majority of the Senate is required for treaty approval. The Senate's main role regarding treaties is approval. While there may be some informal advice - giving during negotiations in practice, the constitutional role is specifically approval. The President of the Senate (the Vice - President) does not sign treaties as part of the Senate's role in the treaty - making process. Negotiating the terms of the treaty is the role of the executive branch (the President and the State Department, etc.), not the Senate.

Answer:

approve international treaties.