Two identical blocks are connected by a light spring. The combination is suspended at rest from a string attached to the ceiling, as shown in the figure-2.190 below. The string breaks suddenly. Immediately after the string breaks:
A. Acceleration of both the blocks would be g downward
B. Acceleration of centre of mass of the combined block system would be g downward
C. Acceleration of upper block would be 2g downward
D. Acceleration of lower block would be g upward
