How did the writers of the U.S. Constitution improve the amendment process from that of the Articles of Confederation?

It required unanimous consent by the states to amend.

It required support of six of the 13 states to amend.

It required support of nine of the 13 states to amend.

It required a two-thirds vote in Congress to propose amendments.

Question

How did the writers of the U.S. Constitution improve the amendment process from that of the Articles of Confederation?

It required unanimous consent by the states to amend.
 
It required support of six of the 13 states to amend.

It required support of nine of the 13 states to amend. 

It required a two-thirds vote in Congress to propose amendments.

anonymous · Answer

D, required a 2/3 vote for congress to approve,

anonymous · Answer

thx @Cman456