Practical Geometry Symmetry & Visualising Solid Shapes

If we rotate a right-angled triangle of height 5 cm and base 3 cm
about its height a full turn, we get
(a) cone of height 5 cm, base 3 cm
(b) triangle of height 5 cm, base 3 cm
(c) cone of height 5 cm, base 6 cm
(d) triangle of height 5 cm, base 6 cm