4. Progesterone is a hormone that helps prepare a woman's body for pregnancy and regulates
menstrual cycles. In a synthesis of progesterone, an alkene with the molecular formula $C_{21}H_{32}O$
was subjected to an ozonolysis process to afford compound B, a triketone that was directly
converted into progesterone.
\text{Compound A}
$C_{21}H_{32}O$