First of all, it can be determined that no matter where the cross section is, the top is leveled (because the whole bottom is leveled), so it is not (4).

Secondly, if the section passes through the central axis, it should obviously be (1) instead of (2), because the "section" is not a "sectional view" and the top line of the other half cannot be seen.

Well, we can already choose here.

As for the comparison between (3) and (5), it is not (3), because the plane that does not pass through the central axis is a hyperbola (one of the definition methods of conic curve). Although (5) is not very standard.

-From (3) and (5), the correctness of (1) can be verified again: if (2) is correct, then (3) and (5) must draw solid lines on both sides and at the top of the graph, which is the sectional view.