Algae which is parasite of tea plant is
Cephaleuros is a genus of parasitic thalloid algae and its common name is red rust. Dichotomous branches are formed in these algae. The alga is parasitic on some important economic plants of the tropics and subtropics such as tea, coffee, mango and guava causing damage limited to the area of algal growth on leaves or killing new shoots, or may be disfiguring fruit. Members of the genera may also grow with a fungus to form lichen, that does not damage the plants. Thus, the correct answer is option A.