The spiders have became resistant to the pesticide.
Seeing that our species is constantly evolving, maybe it is starting to get more uncomfortable to walk on all fours.
The right answer is the option a, part of a binary system<span>. A binary system is two astronomical bodies which orbit one around each other due to the gravitational atraction that they mutually exert on each other. . On the other hand, Sun is a yellow star, a main sequence star and of average absolute magnitude. </span>
)Sexual reproduction maintains a constant level of variation in the population and requires less energy.