A cylinder would seem to fit the given description that has circular parallel bases and a rounded body.
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A triangle with a circular base
A parallelogram, but only if you are counting in base 9.
A cone would fit the given description
A cylinder has a circular cross section that is parallel to its base.
It depends on the base. If the base is an n-sided regular polygon, the pyramid will have n/2 pairs of parallel sides. The number of parallel sides when the base is irregular will depend on the exact details of the base.