Đáp án đúng: B Ta có : $\left\{ \begin{array}{l}y(0)=-4\\y(1)=0\\y'(1)=0\\y''(1)<0\end{array} \right.\,\Leftrightarrow \,\left\{ \begin{array}{l}c=-4\\1+a+b+c=0\\3+2a+b=0\\6+2a<0\end{array} \right.\,\Leftrightarrow \,\left\{ \begin{array}{l}a=-6\\b=9\\c=-4\end{array} \right.$ Do đó $k=y'(-1)=3-2a+b=24$ Đáp án B