Nuclear Material – Definition:\nIn a eukaryotic nucleus, the complex of DNA and associated proteins (primarily histones) is called:

Introduction / Context:
DNA does not exist naked in the nucleus. It is packaged with proteins in an organized structure essential for gene regulation and chromosome architecture.

Given Data / Assumptions:

• We are in a eukaryotic nucleus.
• Proteins involved are predominantly histones, plus non-histone proteins.

Concept / Approach:
DNA winds around histone octamers to form nucleosomes, which fold into higher-order structures. This DNA-protein complex is chromatin. Nucleoplasm is the nuclear matrix/sol; plasmids are extra-chromosomal DNA in prokaryotes; nucleoid refers to prokaryotic DNA region.

Step-by-Step Solution:
1) Identify the described mixture: DNA + proteins.2) In eukaryotes, that definition maps to chromatin.

Verification / Alternative check:
During mitosis, chromatin condenses to visible chromosomes—consistent with the definition.

Why Other Options Are Wrong:
Nucleoplasm is the nuclear fluid. Plasmids and nucleoid are prokaryotic terms.

Common Pitfalls:
Confusing “chromatin” with “chromatid”; a chromatid is one of two identical halves of a replicated chromosome.

Final Answer:
chromatin