Question

the national assembly dissolved and was replaced by
the french republic.
the monarchy.
the senate.
the national convention.

Explanation:

During the French Revolution, the National Assembly was dissolved and replaced by the National Convention in 1792, which oversaw the transition to the First French Republic. The other options are incorrect: the French Republic was the state established, not the direct replacement body; the monarchy had been overthrown prior to this transition; the Senate was not the immediate successor to the National Assembly.

Answer:

the National Convention.