Answer: (2)
The inflorescence is the arrangement of flowers on the floral axis. Cyathium contains a cup-shaped involucre provided with nectar-secreting glands. A female flower is enclosed within the involucre. A number of male flowers surround the female flowers. Hypanthodium is the receptacle forms a hollow cavity and has an apical opening protected by scales. The similarity between the cyathium and hypanthodium inflorescence is the availability of unisexual flower.
