When a Stickleback fish feels threatened, it will flare out its pair of pelvic spines and three dorsal spines, making it difficult for predators to swallow them.
C. Medusa. Everything else on the list is a part of another creature, medusa is the only cnidarian here!
Answer: The correct answer is option a.
Explanation:
Prezygotic isolation is a mechanism by which mating and fertilization is prevented. Thus, it prevents the formation of a zygote.
It can be achieved by various reasons such as temporal differences (difference in mating seasons), habitat isolation, behavioural differences (different mating rituals such as different dance patterns, voice calls, et cetera), mechanical isolation, et cetera.
Thus, different breeding calls prevent the species to interbreed with each which ultimately prevent the formation of zygote formation.
Hence, it is a type of prezygotic isolation.
The rock cycle<span> is a model that describes the formation, breakdown, and reformation of a </span>rock<span> as a result of sedimentary, igneous, and metamorphic processes. All </span>rocks<span> are made up of minerals.</span>