Which of the following is a rational number?

Answer:
B) [tex]-\sqrt{64}[/tex]
Step-by-step explanation:
A rational number, can be expressed as a fraction: [tex]\frac{a}{b}[/tex] where a and b are both integers.
The square root of 64, can be simplified to 8, since 8 * 8 = 64.
So the expression: [tex]-\sqrt{64} = -8[/tex], and 8 is a rational number, since it can be expressed as: [tex]\frac{8}{1}[/tex]