A cylinder.
(This isn't a fake answer.)
a cone
A cone
cone
A cone has one circular base and a vertex that is not on the base.as described on math.com
A cone
a cone
cylinder
A solid figure with one circular base and one curved surface is called a cylinder. In a cylinder, the circular base is parallel to the other circular base (if there is one), and the curved surface connects the edges of the base, forming a three-dimensional shape. If it has only one base, it can be considered a cone, which has a circular base and a single curved surface that narrows to a point.
a cone
A cone has a circular base.
Cone
A solid hemisphere has two surfaces: one curved surface and one flat circular base. The curved surface forms the outer part of the hemisphere, while the flat base is the circular face at the bottom.
A solid hemisphere has two surfaces: one curved surface and one flat circular base. The curved surface is the outer part of the hemisphere, while the flat base is the circular section that sits on a plane.
A cylinder
A cone is a solid with a flat circular base tapering to its vertex or
A cone
A cone would fit the given description.