单选题：The closing of A by B is :

The closing of A by B is :



A.the dilation of A by B followed by the erosion of the result by B
B.the erosion of A by B followed by the dilation of the result by B
C.the dilation of A by B followed by the dilation of the result by B
D.the erosion of A by B followed by the erosion of the result by B


答案：A