I didn't have a great life,but I had what I ----------.

I didn't have a great life,but I had what I __________.
A.had B.did C.was D.owned
可是这里面的had做什么用呢?助动词,实义动词?如果做助动词,那么后面省略了什么?
要是翻译成“拥有”，那为什么不选D owned呢？