4. When counting from 3 to 201 in order, 53 is the 51st number, and when counting from 201 to 3 in reverse order, 53 is the ( )th number.
(A) 146
(B) 147
(C) 148
(D) 149
(E) 150
4. D.

Notice that, in the sequence, if an item is the $i$-th term in order, then it should be the $199+1-i$-th term in reverse order. Therefore,
$$
199+1-51=149 \text {. }
$$