Concept: The question tests on Ratios

Solution: 
Let the length, breadth and height be 8x, 4x and x

Therefore 8x + 4x + x = 13x = 156

x = 12

The dimensions are 96, 48 and 12.

Since the cylinders are kept on the base, the diameter of 1 cylinder = 3 units.

Number of cylinders along the length = 96 / 3 = 32

Number of cylinders along the breadth = 48/3 = 16

Number of cylinders along the height = 12/1 = 12

Total number of cylinders = 32 * 16 * 12 = 6144

Option D