Deriving the Triangle Area Formula Practice Test

Which formula correctly gives the area of a triangle when two sides $a$ and $b$ and their included angle $C$ are known?​​

Triangle $XYZ$ has side $XY=14\text{ cm}$ and side $XZ=10\text{ cm}$. The included angle between them is $\angle X=60^\circ$. Using the given information, what is the area of the triangle?​​​