Read the assertion and reason carefully to mark the correct option in question.

Assertion: Interphase nucleus has a loose and distinct network of fibre called chromatin.

Reason: Chromatin contains $RNA,DNA$ and histone proteins but non-histone proteins are absent.

1. If both assertion and reason are true but the reason is not the correct explanation of the assertion.
2. If both assertion and reason are false.
3. If assertion is true but the reason is false.
4. If both assertion and reason are true and the reason is the correct explanation of the assertion.

The correct option is B If both assertion and reason are false.
Assertion

Interphase nucleus has a loose and distinct network of fibre called chromatin.

Elaboration:

The $G_1,S$, and $G_2$ phases are included in the interphase of the cell cycle. During this phase the cell prepares itself, replicates its $DNA$, and gets ready for mitosis. Genetic material is present in the form of beads-on-string structure inside the nucleus of the cell. This structure is known as chromatin. They form a loose and indistinct structure.

Reason

Chromatin contains $RNA,DNA$ and histone proteins but non-histone proteins are absent.

Elaboration:

Chromatin is a network of nucleoprotein fibres present inside the nucleus. It consists of $DNA$, protein and $RNA$.

The chromatin organisation involves compact packaging of $DNA$ with the help of histone proteins. Additionally, non-histone proteins are present which have a key role in organisation and regulatory functions.

Final answer

(D) If both assertion and reason are false.