If f(x) is discontinuous, determine the reason.[tex]f(x) = \left \{ {{x^2 + 4; x \leq 1} \atop {x+4; x \ \textgreater \ 1}} \right.[/tex]a. f(x) is continuous for all real numbersb. The limit as x approaches 1 does not exist c. f(1) does not equal the limit as x approaches 1 d. f(1) is not defined