Humans, like all mammals, are diploid organisms. This means that we have two copies of each chromosome. In diploid organisms, one somatic cell would have two copies of each gene. This means that in one somatic cell, an individual carries two copies of alleles for long eyelashes, and also two copies of alleles for short eyelashes.
A biotic factor is a living thing that has an impact on another population of living things or on the environment. Abiotic factors do the same thing, but they are non-living. Together, biotic and abiotic factors make up an ecosystem. To survive, biotic factors need abiotic factors.
You are right, it is B because, endocrine glands, as part of the endocrine system, they regulate and maintain a constant equilibrium in our bodies, known as homeostasis.
