Answer:
option 1.
circle
Step-by-step explanation:
A section is formed when a solid shape is sliced into two. A conic section is therefore formed when a cone, is sliced into two.
What determines the shape of the section now, is the angle at which the cone was sliced.
Normally, the base of a cone is a circle. If we slice a cone using a straight line, which runs parallel to its base, we will still get another perfect cone, but with a smaller height.
If we look at the flat portion of the cone after it has been sliced, we will see that the cross-section is a circle.