Eology belongs to which main category of science?

I believe you mean ecology. Ecology belongs to biology.

Ecology is the study of the relationships between different organisms and their environment. Topics from ecology includes such as food webs, cycles (water, carbon, nitrogen,etc), population, pollution, and more.

I’m not really sure

Homologous chromosomes with heterozygous alleles d) heterozygous chromosomes with homozygous alleles