How do we define the terms bull and bear with regard to stock markets?

• A. A bull is an optimistic operator who first buys and then sells shares in expectation of the price going up; a bear is a pessimistic market operator who sells the shares in expectation of buying them back at a lower price
• B. There is nothing significantly different as both operate in the capital market
• C. Bull is one who first sells a share and then buys it at a lower price; bear means one who first buys and then sells it in expectation of prices going up
• D. A bull is ready to buy any share; a bear only deals in government securities