p points are chosen on each of the three coplanar lines. The maximum number of

triangles formed with vertices at these points is

• A

  _$p^3+3p^2$

• B

  _{$\frac{1}{2}\left(p^3\text{+ }p\right)$}

• C

  _{$\frac{p^3}{2}(5p-3)$}

• D

  _$p^2(4p-3)$