The correct option is
C Nucleosomes
Histone are alkaline protein which helps in packaging of the nucleic acid. H2A, H2B, H3 and H4 are core histone protein while H1/H5 are known as the linker histones.
Nucleosome model has a core protein on which the DNA is wrapped spirally. The core particle and the DNA is considered as nucleosome. The two nucleosomes is connected by the linker DNA. The core particle is mainly composed of histone protein. The linker DNA contains H1 or H5 protein.
So, the correct answer is option C.