In which one of the following kinds of organisms is the phenomenon found wherein the female kills the male after copulation?

The behaviour in which a female kills and sometimes eats the male after mating is called sexual cannibalism and is well-documented in spiders. Female black widows and related arachnids have been observed to consume males during or after copulation; western black widow females are known to occasionally ‘snack’ on smaller suitors [1]. Empirical reports and laboratory observations record females cannibalising males during mating in Latrodectus species, with multiple documented instances of males being eaten in copulatory contexts. This extreme post-copulatory killing distinguishes spiders from the other options (dragonfly, honeybee, pit viper), where female-initiated killing of the male after mating is not a characteristic mating strategy.

Sources

1. [1] https://www.nature.com/scitable/blog/student-voices/male_black_widows_sniff_out/