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In general, an option gives to the
buyer the right, but not the obligation, to buy or sell a good, whereas the
option seller must {{U}} (21) {{/U}} accordingly. Many different types of
option contracts exist in the {{U}} (22) {{/U}} world. The two major
types of contracts {{U}} (23) {{/U}} on organized options exchanges are
calls and puts.
A call gives to the buyer of the option contract
the right to buy a specified number of units of an underlying asset, at a
specified price called the exercise or {{U}} (24) {{/U}} price, on or
before a specified date called the expiration date or strike date. A put gives
its the buyer the right to sell a specified number of units of an underlying
asset at a specified price on or before a specified date. In all cases the
{{U}} (25) {{/U}} of the option contract, the writer, is subordinate to
the decision of t
