4. A long straight wire is in the plane of a loop wire, as shown in Fig. 3. The straight wire initially carries no current. While the current i is smoothly increasing from zero, the current in the rectangle loop is


(A) zero
(B) clockwise
(C) counterclockwise
(D) clockwise in the left side and counterclockwise in the right side
(E) counterclockwise in the left side and clockwise in the right side.

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