If x, y, z are three positive integers such that x is greater then y and y is greater than z, then which of the following is definitely true ?

(a) x% of y = $$\frac{xy}{100}$$ and y of z = $$\frac{yz}{100}$$
x > y, y < z
⇒ xy > yz
⇒ $$\frac{xy}{100}$$ > $$\frac{yz}{100}$$
⇒ x% of y > y% of z

(b) y% of x = $$\frac{xy}{100}$$ and z% of y = $$\frac{yz}{100}$$
As proved above, y% of x > z% of y

(c) z% of x = $$\frac{xy}{100}$$ and y% of z = $$\frac{yz}{100}$$
x > y
⇒ xz > yz
⇒ $$\frac{xz}{100}$$ > $$\frac{yz}{100}$$
⇒ z% of x > y% of z