Which of the following causes retinal pigmentation?

Ans. is 'b' i.e., Chloroquine * Chloroquine is a 1st line anti malarial drug, which is an erythrocytic schizonticide.* However, its prolonged use of high doses (as in DLE, rheumatoid arthritis) may cause loss of vision due to retinal damage in the form of retinal pigmentation.* Chloroquine may also cause corneal deposits and affect vision and are reversible on discontinuation.* Loss of hearing, rashes, photoallergy, myopathy, graying of hair may occur.