The correct option is
A Ovary, Style and Stigma
Gynoecium is the fourth whorl of a flower. Its individual unit is called megasporophyll or carpel. It consists of an ovary, stigma, and style. It is the female reproductive organ of the flower. The stigma is the top and sticky portion of a carpel. It is the site of pollination. The style of a carpel is a long tube that connects the stigma to the ovary. Ovary is the lowermost part of the carpel and contains the ovules. Thus the correct answer is option B.