Which of the following could be an example of a function with a range (-∞,a] and a domain [b, ∞) where a > 0 and b > 0?
Aƒ(x)= √(x-a)+b
Bƒ(x)=-√(x-b)+a
Cƒ(x)=-3√(x+a)-b
Dƒ(x)=3√(x+b)-a
Aƒ(x)= √(x-a)+b
Bƒ(x)=-√(x-b)+a
Cƒ(x)=-3√(x+a)-b
Dƒ(x)=3√(x+b)-a