Final answer:
Endophotocoagulation is the technique that uses a laser to treat retinal tears or proliferative diabetic retinopathy. Hence option A is correct.
Step-by-step explanation:
Endophotocoagulation is a technique that utilizes a laser to treat various eye conditions, including retinal tears or proliferative diabetic retinopathy. In this procedure, a laser is used to apply focused and controlled beams of light to coagulate or seal blood vessels in the retina. This helps prevent or treat conditions such as retinal tears and abnormal blood vessel growth associated with proliferative diabetic retinopathy.
The other options are unrelated to the treatment of retinal tears or diabetic retinopathy:
b) keratoplasty: This is a surgical procedure involving the transplantation of the cornea.
c) phacoemulsification: This is a surgical technique used for cataract removal.
d) trephination: This is a procedure involving the removal of a circular section of tissue or bone, and it is not specific to retinal conditions.
Hence option A is correct.