Correct Answer :
C. Gymnosperms
Gymnosperms are seed-bearing vascular plants, such as cycads, ginkgo, yews and conifers, in which the ovules or seeds are not enclosed in an ovary. Gymnosperm seeds develop either on the surface of scale or leaf-like appendages of cones or at the end of short stalk. The largest group of living gymnosperms are the conifers (pines, cypresses and relatives) and the smallest is ginkgo, a single living plant species found in China.