The question is incomplete as it does not have the options which are:
a. stramenopile
b. red alga
c. choanoflagellate
d. green alga
e. brown alga
Answer:
b. red alga
Step-by-step explanation:
In the given question, seaweed has been growing in a tropical sea which on analysis was found that it contains the two photosynthetic pigments called the chlorophyll a and the phycobilins.
Phycobilines ate the bilin or tetrapyrrole molecules which act as an accessory photoreceptors pigment in the algae which can help absorb the wavelength of red, orange and green light.
The phycobilins are abundant in the red algae and the cyanobacteria but since the chlorophyll a and the phycobilins are mentioned therefore red algae is the most appropriate answer.
Thus, Option- B is correct.