The biological species concept is least relevant to which of the following groups of organisms?
a. Birds Mammals that form monogamous pair bonds
b. Asexual fungi
c. Fungi that engage in sexual reproduction
d. Cryptic species

b) is the correct option

Explanation:

The biological species concept defines a species as a group of individuals living in one or more populations that can potentially interbreed to produce healthy, fertile offspring

The biological species concept connects the idea of a species to the process of evolutionBecause members of a species can interbreed, the species as a whole has a common gene pool, a collection of gene variantsIn order to be considered to be a single species in the biological species concept, a group of organisms must produce healthy, fertile offspring when they interbreedIn some other cases, organisms of different species can mate and produce healthy offspring, but the offspring are infertile, can’t reproduce

Hence it includes the groups which are reproductively isolated so asexual fungi will be least relevant to this group