The calyx is a sepal present in the outer whorl of a flower that is green in color and protects the flower. Based on the calyx, flowers are of two types- Gamosepalous and polysepalous. Gamosepalous is a condition in which sepals are fused or united whereas in Polysepalous sepals are free. Complete answer:
> Option A- Gamosepalous
In gamosepalous flowers, the calyx consists of fused sepals. The calyx is the term given to all the sepals collectively of the same plant. The sepals refer to a leaf-shaped structure found in flowering plants or angiosperms. It is a modified leaf present on the outermost part of the flower. The main function of sepals is to give support and protection to a flower bud when it's closed around it until it’s ready to bloom. Sepals can be of a wide variety, from long to short, thick to thin, fused together or separated, and are found in different numbers. These fused together sepals are found in gamosepalous flowers. Example- Periwinkle and Hibiscus
> Option B- Gamopetalous
It is a condition in which petals are wholly or partially fused in such a way that the corolla takes the form of a tube, trumpet, channel, or similarly nearly-rigid structure.
> Option C- Polysepalous
Pol-i-sep′a-lies, adj. having the sepals separate from each other. It describes a condition in which a flower that possesses a calyx consists of separate sepals.
> Option D- polypetalous
In this condition, the flower consists of a corolla composed of many separate or distinct petals. Petaled, petalled, petalous - (terms of flowers) refers to having petals.Hence, The correct answer is option (A).Note:
The sepals and petals together form the perianth or floral envelope. The sepals are usually greenish. They often resemble reduced leaves. While the petals are usually colorful and showy. When the sepals of a flower are fused, they are called gamosepalous. Eg: Hibiscus and periwinkle and when the sepals of a flower are free, they are called polysepalous. Eg: Rose and Southern magnolia.