The cerebral hemispheres of a rat are connected by:

Match the following human spinal nerves in column-$I$ with the number of pairs in column-$II$ and choose the correct option.

Column-$I$	Column-$II$
$(a)$ Cervical nerves	$(i) \; 5$ pairs
$(b)$ Thoracic nerves	$(ii) \; 1$ pair
$(c)$ Lumbar nerves	$(iii) \; 12$ pairs
$(d)$ Coccygeal nerves	$(iv) \; 8$ pairs

What is white matter?

Which of the following produces cerebrospinal fluid $(CSF)$?

The parasympathetic nervous system increases the activity of which of the following?

Given below are two statements:
Statement $I$: The cerebral hemispheres are connected by a nerve tract known as the corpus callosum.
Statement $II$: The brain stem consists of the medulla oblongata,pons,and cerebrum.
In the light of the above statements,choose the most appropriate answer from the options given below: