8. In $\triangle A B C$, it is known that $B = 120 ^ { \circ } , A C = \sqrt { 19 } , A B = 2$, then $B C =$ ( ) A. 1 B. $\sqrt { 2 }$ C. $\sqrt { 5 }$ D. 3
8. In $\triangle A B C$, it is known that $B = 120 ^ { \circ } , A C = \sqrt { 19 } , A B = 2$, then $B C =$ ( )\\
A. 1\\
B. $\sqrt { 2 }$\\
C. $\sqrt { 5 }$\\
D. 3