What is genetic background?

The term "genetic background" refers specifically to the genetic constitution of an organism, which includes all of the alleles and genes inherited from its ancestors. This genetic makeup can greatly influence how an organism responds to environmental factors. For instance, different genetic backgrounds can lead to variations in traits, behaviors, and resistances to diseases, all of which are crucial in determining how an organism interacts with its surroundings.

In microgenetics, understanding an organism's genetic background is essential for predicting how traits may be expressed under different environmental conditions. The genetic background interacts with these conditions to determine the phenotype, or observable characteristics, of the organism. Thus, choice B accurately captures the essence of genetic background and its role in shaping organismal responses to environmental influences.