A parasite that is successful helps its host. B does minimal harm to its host. C murders its host. D has a longer lifespan than its host. E increases the size of its host's heart. F parasites are abundant in nature. G knows how to avoid being killed by their host. H is infectious like a virus. I uses insects as transport hosts. J parasites are found in all phyla of life. K are responsible for a large proportion of all deaths in humans. L cause more death than cancer. M are involved in major evolutionary transitions. N are important in regulating the immune system. O are used by I as a defence mechanism against other parasites! P are effective tools for preventing disease and promoting health. Q are useful in treating diseases, such as malaria and leishmaniasis. R are able to invade new cells. S can live inside other organisms, including humans. T are involved in complex behaviors such as mating and social interaction. U have been implicated in the evolution of intelligence. V are involved in ecological processes such as energy flow through ecosystems and speciation.