Answer:
B. Australia is isolated
Explanation:
They originated in South America and spread throughout the world, but due to competition on other continents, the other marsupials died out, while the ones on Australia lived.
Answer:
The correct answer would be meiosis.
In diploid organisms, meiosis is the process that results in the formation of four haploid daughter cells from single diploid parent cell. Each of the daughter cell contains half the number of chromosomes present in parent cell.
It results in the formation of haploid gametes (sperm in males and eggs in females) which is essential in the process of sexual reproduction.
The fusion of gametes results in the formation of diploid zygote that is, maintains the diploid nature of the organism.
Hence, in absence of meiotic division the chromosomal number would keep on doubling after each generation.
In addition, crossing over (exchange of genetic material between non-sister chromatids) also takes in the prophase-I of meiosis I. It increases the genetic variation within organisms of the species. It may add survival adaptations to the population.
They have a light complexion, may have not wore sunscreen, or was in direct contact with the sun all day.