Answer:
B. cylinder
Explanation:
Any cross section of a cylinder that is parallel to the base will be a circle of the same radius as the cylinder.
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Various cross sections of any of these figures can be made to be non-uniform. They can also be made to be uniform, if you put restrictions on how the section is done.
For example, a right pyramid will have uniform cross sections, if they are all through the point and perpendicular to the base and one edge. Similarly, a sphere will have uniform cross sections if they are all taken at the same distance from the center of the sphere.
We assume the problem intends no particular restrictions, though we would like to note that cylinder cross sections are uniform only when parallel to each other without intersecting a base.