Explain why the function is discontinuous at the given number a. (Select all that apply.) f(x) = {1 x+3 if x ≠ −3 1 if x = −3 a = −3 f(−3) is defined and limx→−3 f(x) is finite, but they are not equal. f(−3) is undefined. limx→−3 f(x) is not finite. limx→ −3+f(x) and limx→−3 −f(x) are finite, but are not equal. none of the above Sketch the graph of the function.