Let $f ( x ) = \left\{ \begin{array} { c c } 3 x & - 1 < x < 0 \\x + 4 & 0 \leq x < 4 \\2 x & 4 < x \leq 6\end{array} \right.$

Multiple Choice

Let $f ( x ) = \left\{ \begin{array} { c c } 3 x & - 1 < x < 0 \\x + 4 & 0 \leq x < 4 \\2 x & 4 < x \leq 6\end{array} \right.$ Then ƒ is continuous at 4 if ƒ(4) is defined as

A) 4
B) 5
C) 6
D) 7
E) 8