The right option is; chromosome
Chromosomes are thread-like structures in which DNA molecule (nucleic acid) and protein (histones) are packaged in the cell’s nucleus. Chromosomes functions by carrying genetic information in the form of genes. Each chromosome possess a constriction point (centromere), which separate chromosomes into two parts. Chromosomes may be circular in shape (such as in prokaryotic cells), or linear in shape (such as in eukaryotic cells).