What kind of mimicry is it when houseflies try to imitate wasps?

The correct answer is Mullerian mimicry.

Explanation:

Mullerian mimicry is mimicry in which 2 or more harmful animals/insects develop the same appearances for protecting themselves by protective device, the theory is that if a predator species learns to avoid 1 of harmful species of prey, it will also avoid the harmless species that mimic such appearance.

In the case of houseflies, they develop such similar appearance as the wasp but in reality, they are harmless but wasp can sting and harmful. Due to their appearance and mimicry predators also avoid houseflies

Thus, the correct answer is Mullerian mimicry.

organisms that lack symmetry are called asymmetrical and belong to phylum porifera/sponges.

organisms with specialized stinging cells belong to phylum cnidaria. stinging cells are called cnidoblast cells.

cnidarians show two morphological forms : polyp (sessile) and medusa (mobile)

filter feeding is observed in porifera members.  

alternation of generation is observed in coelenterata or cnidaria. there is alternation of asexual polyp form and sexual medusoid form. it is also referred as metagenesis.

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