The executive office agency responsible for preparing the president’s budget forecasts and proposals is the

Council of economic advisers, is the right answer.

Explanation:

The Council of Economic Advisers is an office within the President Executive Office. This agency was established in the year 1946. The main objective of this agency is to advise the U.S. President on significant economic policy. This agency presents a leading experimental analysis for the White House and makes the year-end Economic Report of the President.