Joker found one of the biggest diamonds in the world in his own backyard. He sold the stone to a diamond dealer for over three hundred thousand dollars. In New York, the diamond was resold，this time for almost eight hundred thousand dollars. The true value of a diamond is never known until it has been cut. Once cut successfully, its value can increase a thousand times. It’s easy to understand why the owner of the Joker diamond went to the best diamond cutter he knew, Kaplan. The cutter studied the diamond for twelve whole months.
When he felt he was ready to start work, he discovered a flaw （瑕疵）. He had to begin with his calculations all over again, or he might have made the stone useless. Six more months passed, and Kaplan finally said to the owner, “I am ready to start my work. There will be one excellent diamond that will be comparable to any in the world, plus eleven small diamonds of first-class quality. ” Kaplan waited a few more days until he felt he was in the best physical and mental （精神的） condition possible. He picked up his tools and held his breath as he made the first blow. The diamond split （切开） exactly as he promised.
A diamond dealer is a person ______,

A．in the diamond business	B．who stores diamonds
C．who cuts diamonds	D．who sells diamonds

The owner of the Joker diamond thought that if the diamond was cut successfully, it might be worth ________.

A．$300, 000	B．$500, 000
C．$300, 000, 000	D．$800, 000, 000

Kaplan studied the diamond for ________.

A．one year	B．more than half a year
C．over eighteen months	D．more than two years