Respuesta :
Yes it is true that point , line and pair of intersecting lines are special cases of conic sections
They are actually degenerate cases of intersection that occurs in special conditions.
Lets get into a bit detail one by one
A single point - when the plane which cuts the surface of cone only passes through apex
Again when the plane passes through apex and another point on the cone
it produces one straight line or two intersecting straight lines.
