How do self-interest and competition affect free markets?

They work together to keep prices high. They work together to regulate supply, demand, and prices. They represent the opposing interests of consumers and producers.

Explanation:

every society, in order to meet the needs of it's people, has to answer three basic questions:

- what should we produce?

- how should we produce it?

- for whom should we produce it?

this questions must be answered in order to, option b, aid in production decisions.

every country can't produce everything, no matter how rich their land is. it may be a matter of technology, resources or geographical conditions. so, these three questions must be resolved in order to get the most of the production of each land.

hope this !

i have to go with a for this one