The correct option is B Diosgenine
Dioscorea spp, commonly known as Yams belong to family Dioscoreaceae. The true Yams, belonging to the genus Dioscorea are grown throughout the wetter tropics for their stem tubers. They are important sources of food for millions of people in the tropics, especially in the south western Nigeria where they are a staple food. Dioscorea is a large genus with about 600 tropical or subtropical species. Yams constitute a cheap source of carbohydrate foods and are nutritionally better than cassava because of a higher proportion of proteins. They also contain more of vitamin C.
In recent years, wild species have been much used for the extraction of steroidal sapogenins which can be converted into cortisone, into the testosterone (male hormone) and the oestrogens as well as progesterones (female hormones). Three wild species particularly D. composita, D floribunda, D. mexicana have been used as a source material for the manufacture of oral contraceptives. In this way this genus has contributed significantly towards controlling the world population.