What type of life cycle do cestodes (tapeworms) typically exhibit?

Cestodes, commonly known as tapeworms, typically exhibit an indirect life cycle. This involves multiple hosts during different stages of their life. The adult tapeworm usually resides in the intestines of a definitive host, often a carnivore, where it can reproduce and produce eggs. These eggs are then excreted in the host's feces and can be ingested by an intermediate host, often a herbivore or omnivore, where the larval forms develop.

This complex relationship between the definitive host and one or more intermediate hosts is a hallmark of an indirect life cycle, distinguishing it from a direct life cycle, where a parasite can complete its life cycle within a single host. In terms of cestodes specifically, their reliance on different hosts for various stages of development is critical for their transmission and survival, making the indirect life cycle the correct answer. The other options do not accurately describe the reproductive strategies and host relationships typical of tapeworms.