A call option gives the holder the right, but not the obligation, to buy the underlying security at a predetermined priced, called the strike price, by a set date.
A cash settled option is an option that settles in cash instead of an underlying security. The most typical example of a cash settled option is an index option.
A clearing corporation becomes the buyer for every seller and seller for every buyer in an organized options market. A clearing corporation is designed to ensure standardized contracts and to remove default risk for the counterparties.
Gross income is constructively received when it is credited to the taxpayer's account, set aside, or otherwise made available so that it may be drawn upon.
This is where a futures contract is more expensive than the spot price, usually because of the cost of storing the underlying commodity. This is the opposite of backwardation.