I think it is C because i got this same exact question in my class
A population that has been isolated, especially a smaller one, could have a high level of homozygosity and therefore not a lot of genetic variation. Gene flow between such populations can increase the level of heterozygosity, and therefore up genetic variation.
C. <span>more producers than consumers
</span><span>Because for example one large eagle needs lots of small sparrows to eat. There is usually a food pyramid so for example you could display it along the lines of 1,000 worms are eaten by 20 sparrows which are eaten by 1 eagle. Its just the way things are. It is a fine balance. if you went up to two eagles on same land they would run out of food quickly and then would either starve or have to move on and using up all the food doesnt help them so it needs to be in a fine balance. A balanced ecosystem.</span>