15. Commercial agar is obtained from A.Chlorella B.Gracilaria C.Parphyro D.Volvox
Answer: Option B Solution: The gelling agent in agar is an unbranched polysaccharide obtained from the cell walls of some species of red algae, primarily from tengusa (Gelidiaceae) and ogonori (Gracilaria). For commercial purposes, it is derived primarily from ogonori.
