A circular shaft fixed at, A has diameter D for half of its length and diameter D/2 over the other half, as shown in the below figure. If the rotation of B relative to A is 0.1 radian, the rotation of C relative to B will be

A. 0.4 radian

B. 0.8 radian

C. 1.6 radian

D. 3.2 radian

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