Crossing dissimilar individuals
with similar characteristics is called hybridization. Hybridization is the act
of producing offspring through mating two parents
from different breeds or varieties. Offspring produced by hybridization may be
fertile, partially fertile, or sterile. The concept of hybridization differs in animal and plant breeding.
The answer is "B. Marsupials". Marsupials undergo relatively premature births compared to many other species, and although this puts the baby at risk, it lessens the risks for the mother.