Pheasants are a type of bird. two male pheasants and six female pheasants were introduced onto an island with abundant food and few predators. within six breeding seasons, the pheasant population increased from eight birds to two thousand birds. over time, however, the growth rate of the population slowed. which of the following statements describes the most likely reason for this decrease in population growth rate? *

a.)females built smaller nests, which decreased the birth rate.
b.)competition for resources increased, which increased the death rate.
c.)large numbers of birds needed mates, which increased the immigration rate.
d.)fewer eggs hatched each successive year, which decreased the emigration rate.