Chromosome is not only responsible for genetic material. Chromatin is that substance which consists of protein and DNA. Here DNA carries genetic instruction. Histones are main proteins of chromatin. It is also called the packaging of element for the DNA.
In two forms chromatin exist. One is euchromatin and another is heterochromatin. Euchromatin is less condensed and it can be transcribed. Heterochromatin is highly condensed and typically not transcribed. Chromosomal pathway regulates spindle assembly.
Facilitated diffusion is a diffusion mechanism facilitated by membrane transporters. it's the spontaneous passage of molecules or ions (like the passive diffusion) through a biological membrane through transport molecules (unlike passive diffusion). This process does not consume energy (like the passive diffusion) and therefore does not involve active transportation.
The reason for Ovum being the correct answer, is because the Ovum is in the lower plant structure, and is the structure that is needed to be fertilized to reproduce gametes.