A circular disc A of radius r is made from aniron plate of thickness t and nother circular disc B of rdius 4r is made fro an iron plate of thickness t/4. The relatiion between the moments of inertia `I_A and I_B` is
A. `I_AgtI_B`
B. `I_A=I_B`
C. `I_AltI_B`
D. depends on the actual values of t and r