Executive agreements differ from formal treaties in that they

Option 3 is the answer - Do not have to be approved by the senate

Explanation:

In executive agreement, two or more heads of nations come together to form these agreements that are politically binding. They are not like treaties formally drafted as an international agreement or pact between sovereign states and international organisations that would require the advice and approvals of two-thirds of the senate before it can be effective (as seen in the U. S).