Least and Most restrictive
Tariffs
Subsides
Sanctions
Embargos

Answer:
Least - Subsidies
Most - Embargos
Explanation:
All of the options are the things that a government can do to limit the amount of trades with another country.
In subsidies, the local government provided helps for local businesses to compete with the products from another country. This does not necessarily made any direct restriction to the foreign products
In Embargoes, a government completely prohibited any form of economic transaction with another country. usually, this only be done if two countries are involved in a war.