A socialist economy is characterized by:

A. an extensive reliance on markets to allocate final goods and services.
B. an extensive reliance on the profit motive to govern resource allocation decisions
C. elimination of the problem of scarcity since all basic necessities are available to all citizens.
D. public ownership of productive resources.

I'm not sure which answer to choose?

Which words don't you understand?

I know it's not C or D, I'm stuck between the others

You need to go back and study your text materials -- or study this site.

http://en.wikipedia.org/wiki/Socialist_economics

so it's D then?

Yes.

A socialist market is characterized by public (government) ownership of key resources.

thanks!

You're welcome.