What is the most important aspect of natural selection

A)  aggressive interactions with members of other species 
B)  passing on genes to the next generation 
C)  locating a source of food 
D)  establishing a territory

The most important aspect of natural selection is passing on genes to the next generation. This is because natural selection is a mechanism that drives the evolution of species over time. The genes that confer advantageous traits are more likely to be passed on to future generations, leading to a gradual change in the genetic makeup of a population. Aggressive interactions with members of other species, locating a source of food, and establishing a territory are all important aspects of an organism's survival, but they are not the most important aspect of natural selection.