Final answer:
King Louis XVI's treasonous acts included declaring the National Assembly unconstitutional (option b) and attempting to escape France, leading to his trial and execution by the National Convention.
Step-by-step explanation:
The treasonous acts committed by King Louis XVI during the French Revolution included declaring the National Assembly unconstitutional, attempting to escape France, and implicitly conspiring with foreign monarchies to restore his power against the revolutionary government. Although he was initially supportive of some reforms, Louis XVI's escape attempt in June 1791, known as the Flight to Varennes, ultimately revealed his true opposition to the Revolution, which led to increasing distrust among the revolutionaries. His attempt to flee France with his family was seen as an act of betrayal and was considered an act of treason. The National Convention, after its formation, put Louis on trial and found him guilty of treason, resulting in his execution in January 1793.