Identify an organism that exhibits metagenesis.

Correct option is A

The correct answer is (a) Obelia.
 Obelia is a genus of hydrozoans that exhibits metagenesis, also known as alternation of generations.
 In Obelia, the life cycle alternates between asexual polypoid and sexual medusoid forms.
 The polyp stage reproduces asexually by budding to form medusae, while the medusae reproduce sexually to produce larvae that develop into new polyps.
Information Booster:
 Spongilla: A genus of freshwater sponges that do not exhibit metagenesis; they primarily reproduce asexually by budding or gemmules.
 Sycon: A genus of calcareous sponges that reproduce both sexually and asexually but do not exhibit metagenesis.
 Euspongia: A genus of demosponges, commonly known as bath sponges, which reproduce asexually by budding and do not exhibit metagenesis.