What tool would a nation avoid using when protecting domestic industries and businesses
a. tariff
b. subsidy
c. free trade
d. quota
pls .

I believe it would be D.  Quota

Explanation:

there will be a fixed min or max number for a particular group of people allowed to do something; i.e immigrants entering the country, workers taking a job, students enrolled for a course.

Tariff is a tool would a nation avoid using when protecting domestic industries and businesses.

Option A

Explanation:

Tariffs can be identified as taxes that are essential, tariffs are marked as duties which are placed on goods that are to be imported. This tariffs are services made by a government that is domestic, the services implied by this government are placed on good products which are also domestic for domestic customers, this makes imported goods expensive.  

The tariffs are a tool made by the political body hence therefore it is a political tool. Throughout time tariffs have been used to control the importation of goods and helps to determine which nation will have a grant favorable for most conditions of trading.  

the secretary of state, appointed by the president with the advice and consent of the senate, is the president's chief foreign affairs adviser. the secretary carries out the president's foreign policies through the state department and the foreign service of the united states.

giant impact theory - the moon was formed from the collision between earth and another mars-sized body.

colliding planetesimals hypothesis - the moon was formed from the same cloud of material as earth.

capture hypothesis - the moon was locked into orbit by earths gravity as it was passing by it.

accretion hypothesis - the moon was formed from collisions and combining of planetesimals.

i think this is right, if not and you know better let me know.