Which action contributed to the Southern belief that their economy was threatened? The founding of the Republican party
The finalization of the Missouri Compromise
The support of popular sovereignty in territories
The approval of protective tariffs on manufactured goods

The approval of protective tariffs on manufactured goods contributed to the belief that their economy was threatened. Option D is correct.

The people in the south believed that their economy was threatened because, there was an approval of tariffs on goods.

They already had water bodies that they could use to transport their goods, They were then opposed to paying tariffs on roads and canals because they felt that they gave them no benefits.

They wanted a situation where even though they paid these tariffs they would derive some economic benefits too.

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it is not option D

Explanation:

I did the assignment and did not get any points for the question

answer:

the majority of cambodians living today were born after the khmer rouge was ousted in 1979 and some who survived can forget how bad it was. when khmer rouge forces seized phnom penh on april 17, 1975, the couple was living with eight of their children in a rural town called kampong chhnang.

explanation:

the indians crossed artificial boundaries, setting the stage for conflict