When the president makes a treaty, it must be approved by:

The correct answer is: D. the Senate

When the president makes a treaty, it must be approved by the Senate. According to the U.S. Constitution, the president negotiates treaties, but they require ratification by a two-thirds majority of the Senate to be considered valid. This process ensures that treaties reflect a broad consensus among the elected representatives of the people. If you have more questions or need further clarification, feel free to ask!