G(x)=(x+5)^2-6

How exactly do I find out which answer is correct? I would appreciate if I told on how I go about finding the right answer.

a. Domain = all real numbers; Range = all real numbers greater than or equal to 6.

b. Domain = all real numbers greater than -5; Range = all real numbers less than -6.

c. Domain = all real numbers; Range = all real numbers greater than or equal to -6.

d. Domain = all real numbers; Range = all real numbers.