Explanation:

- Gifts: These are usually one-time transfers with no expectation of return. They can occasionally contribute to foreign exchange if they come from overseas.

- Donations given: When someone donates from abroad, it may bring foreign exchange into the country. However, this is not a consistent or primary source.

- Imports: This is when goods and services are bought from other countries and usually involve spending foreign exchange, not earning it.

- Exports: When a country sells goods and services abroad, it earns foreign currency. This is a primary source of foreign exchange.