The enzyme which converts 6-phosphogluconolactone to 6-phosphogluconate is
Ribulose-5-phosphate isomerase
Transaldolase
Glucose-6-phosphate dehydrogenase
gluconolactonase
The enzyme which converts 6-phosphogluconolactone to 6-phosphogluconate is gluconolactonase
Hence, the correct option is d.