Final answer:
Colchicine is a chemical agent used to induce polyploidy, a condition where an organism has extra sets of chromosomes, which is particularly common in plants.
Step-by-step explanation:
Among the agents listed for promoting polyploidy, Colchicine is a commonly used compound. Polyploidy is a condition where an organism has extra sets of chromosomes. While it's relatively rare in animals, with a few examples in flatworms, crustaceans, amphibians, fish, and lizards, polyploidy is quite common in the plant kingdom. Polyploid plants are larger and more robust than those with the normal number of chromosome sets, called euploids. Colchicine is used to induce polyploidy by disrupting the normal formation of the spindle fibers during cell division, which prevents the chromosomes from separating normally during meiosis or mitosis. By doing so, it can double the chromosome number, effectively creating a polyploid organism.