Which act of Congress restricted the president's power to commit troops to foreign countries without congressional approval?

The correct answer is the War Powers Act of 1973.

In this law, the power of the president to commit troops is limited. For example, the president must inform Congress 2 days before he/she decides to commit troops to another country or have them involved in some military action. However, the troops are only allowed to stay in that place for 60 days unless Congress approves the action made by the president. If Congress does not approve, then the troops have one month to be removed.