JEE Math Practice Question

Let f : R $$ \to $$ R be a function defined as $$f(x) = \left\{ {\begin{matrix} 5 & ; & {x \le 1} \\ {a + bx} & ; & {1 < x < 3} \\ {b + 5x} & ; & {3 \le x < 5} \\ {30} & ; & {x \ge 5} \\ \end{matrix} } \right.$$ Then, f is

1. A.continuous if a = 0 and b = 5
2. B.continuous if a = –5 and b = 10
3. C.continuous if a = 5 and b = 5
4. D.not continuous for any values of a and b