Tariffs, quotas, and subsidies are examples of

Trade Barriers

Explanation:

Tariffs, quotas, and subsidies are examples of trade barriers. Trade barriers is a step taken by different countries to protect their own citizens jobs by limiting other countries to sell foreign produced goods in some way so that goods produced at home are more appealing to the consumer.

d. new methods of assembly are introduced.

explanation:

this allows for the goods to be made on a larger scale. not faster because now it is shown to be made better, hence the greater productivity in the question. it is calling for something new to be introduced.