Which of these is a condition that makes flowers invariably autogamous?

Options

A. Dioecy
B. Self incompatibility
C. Cleistogamy
D. Xenogamy

Answer

C

Explanation

Autogamy is possible only when anter and stigma are close together and there is synchrony in pollen release and stigma receptivity. As is case of cleistogamous flowers, the flowers remain closed so that anthers and stigmas are never exposed. The flowers undergo only self pollination. No external pollinating agency is required.