Answer:
It is A. Triangle If it's Above the red line If its below the red line B. Trapezoid.
Step-by-step explanation:
If you look at the red line, and see the two shapes you can see a Triangle, and a trapezoid, but a trapezoid can not look tall, a trapezoid has to have a wide area, and a triangle can be any length for an example think, thin, wide, tall, skinny, acute angle, and a abuse angle so your answer would be A. Hope I helped you!
Trapezoid explanation : When you look at the bottom you can see the shape of the trapezoid it might look funny, but a trapezoid can be anything like skinny, tall, acute angle just like a triangle.
of the cylinder by
and 
, and parameterize the disks 
as
and 
.
