In bacterial photosynthesis, photosystem involved is/are

Options

(a) Only PS-I
(b) Only PS-II
(c) Both PS-I and PS-II
(d) Either PS-I or PS-II

Correct Answer:

Either PS-I or PS-II

Explanation:

In bacteria only one photosystem, i.e., then photosystem-I or photosystem-II is present but oxygen evolution does not take place because they use H₂S as an electron donor.