Which of the Following Are Correct? Please Select All That

Which of the following are correct? Please select all that apply.

A) Subsidies are government payments to domestic producers, in the form of cash grants, low-interest loans, and tax relief.
B) Quantitative restrictions or quotas restrict the quantity of imports in order to protect the market share of domestic firms.
C) Tariff barriers can affect both merchandise and trade in services.
D) Quantitative restrictions or quotas are enforced by issuing licenses to a group of firms