"I've been researching Alzheimer’s disease for decades," the doctor said, but I still have so many unanswered questions." a. been researching
b. Alzheimer’s
c. said, but
d. No error

C

Explanation:

Needs quotations

the narrator closes the lantern tightly so the old man is

not awakened by the bright light

explanation:

b. brooks wrote about the same type of neighborhood in which she grew up.