Which of these sets of numbers contain all rational numbers?

A. π, 1/2, - 13

B. - 3.0541 ...,√99, 0.14363

C. - 6, - √225, 4 7/8

D. √21, 0.75, 0

The answer is C, - 6, - √225, 4 7/8.

Rational means that the number can be expressed as a fraction and integer numerators and denominators. - 6 and 4 7/8 can clearly be expressed as a fraction. - 6 can be expressed as - 6/1 and 4 7/8 can be expressed as 39/8.

-√225 is equivalent to - 15, which is rational.

A is wrong because the number includes Pi.

B is wrong because - 3.0541 never ends and √99 is irrational.

D is wrong because √21 is also irrational.