Question

Which one of the following is example of species that breed in captivity and produce infertile hybrids?
(A) Mallard (a duck) and the pin tail duck
(B) Male donkey and female horse
(C) Polar bear and the Alaskan brown bear
(D) Platy and sword tail fishes

Answer 1

Hint: According to biological concept of species-organisms which can interbreed among themselves and produce fertile offsprings are known as species. So, if two organisms produce a sterile offspring on breeding them together then those two organisms are two different species.

Complete Step by Step Answer:
Technically, inbreeding is the mating of animals that are more closely related to one another than the average relationship within the breed or population in question. Practically, the offspring of two mated individuals would be regarded as outbreds if they did not share a common ancestor within the previous five or six generations. Outcrossing, also known as outbreeding, allogamy, or xenogamy, is the transfer of gametes from one genetically distinct individual to another. Outbreeding generally benefits a population by encouraging a rise in phenotypic diversity.

Crossing two species from the same genus is referred to as interspecific hybridization. This makes it possible to harness advantageous genes from uncultivated, wild species to benefit the cultivated species. The Pisum species all have a similar karyotype and are diploid self-pollinators. Interspecific hybridization refers to mating between male and female animals of two different species. The Mule, a hybrid between a female horse and a male donkey, is the best illustration of how two distinct species can coexist successfully.
So, option (B) is correct.

Note: Both mule and hinny are sterile hybrids of horse and donkey, but one reversing the gender of parents we can get mule and hinny. Mule: A female horse and a donkey stallion who have mated. Mules typically have a horse's body with a donkey's head. Hinny: The offspring of a male horse and a female donkey.