$A$ perfectly diamagnetic sphere has a small spherical cavity at its centre, which is filled with a paramagnetic substance. The whole system is placed in a uniform magnetic field $\overrightarrow{B}$. Then the field inside the paramagnetic substance is:

• A
  $Zero$
• B
  $\overrightarrow{B}$
• C
  much larger than $|\overrightarrow{B}|$ but opposite to $\overrightarrow{B}$
• D
  much larger than $|\overrightarrow{B}|$ and parallel to $\overrightarrow{B}$