How many paying stones, each measuring 4 m * 2 m are required to pave a rectangular court yard 40 m long and 20 m board?	Choose the correct choice from the following
A) 99	B) 18	C) 100	D) 17	E) 12

Rationale: "40 * 20 = 4 * 2 * x = > x = 100 answer : c"
Answer: C