What is the following statements is not correct regarding `NO_2` molecule :-
| A. |
Paramagnetic behaviour decreases when it undergoes in dimerisation |
| B. |
It is coloured in its dimeric form |
 |
| C. |
The colour is due to the presence of unpaired electron |
| D. |
The free electron is present in one of the `sp^2` hybrid orbital |