卵巢性激素生物合成途径中，哪项是终末产物（）

A.孕烯醇酮

B.去氢表雄酮

C.睾酮

D.雄烯二酮

E.雌二醇

（）the concert had begun did we realize what a splendid show it was going to be.

A.No sooner

B.Only after

C.Hardly

D.Scarcely