A 3 year old boy is brought to you by the parents with the complains of failure to thrive. The boy also seemed to have language development delay. You found that the boy is lethargic. On examination of the peripheral blood you found megaloblastic anemia. On further examination you found increased orotic acid level in the blood. Blood urea, creatinine level are normal. Which enzyme activity is decreased in this boy?
.
a) Carbamoyl phosphate synthase I
b) UMP synthase
c) Ornithine transcarbamylase
d) Inosine dehydrogenase
e) methylmalonyl Co A mutase
f) methionine synthase