Assertion : A typical angiosperm anther is bilobed  .

Reason : Each anther  lobe having two theca, i.e., they are dithecous .
 

Both Assertion (A) and Reason (R) are correct and R is the correct explanation of A.

• The anther of androecium of angiospermic flowers are bilobed and each lobe is divided into two parts or theca. Thus, the anther of angiospermic flowers are called dithecous
• A typical microsporangium is surrounded by four layers - epidermis, endothecium, middle layer and tapetum.
• The outer 3 layers ie., epidermis, endothecium and middle layer are protective in function and help in dehiscence of anther to release pollen grains.
• Tapetum (innermost layer) nourishes the developing pollen grains