The correct option is
A Carnivorous
Obelia is a marine colonial trimorphic hydrozoan. It shows the presence of polyp, medusa and blastostyle stages in its life history. It is abundant in both Atlantic and Pacific coastal waters. A fully grown
Obelia medusa is a radially symmetrical tiny umbrella, measuring 1 or 2 mm in diameter. Medusa is carnivorous and feeds on planktons.
So, the correct answer is option A.