LASER EYE SURGERIES, ONCE CONSIDERED RISKY AND DANGEROUS, ____ THAT 90 PERCENT OF RECIPIENTS CAN SEE VERY WELL AFTER THE OPERATION

35. Laser eye surgeries, once considered risky and dangerous, ____ that 90 percent of recipients can see very well

after the operation.

A. which are now so successful

B. is now so successful

C. they are now so successful

D. are now so successful