According to some theorists, the difference between speculation and gambling is:

I. The outcome for a gambler is the thrill of the risk so gambling is a form of entertainment

II. Speculators accept a certain level of risk which must be commensurate with the level of return.

III. The belief that commensurate gain relative to risk is a constant, but gambling accepts risk for its own sake.

IV. Both gamblers and speculators have heterogeneous expectations

1. I and II
2. III and IV
3. I and IV
4. II and III