which of the following are true about the CERE – 110 treatment used on Alzheimer's disease patients in the phase 2 clinical trial? It was an AVI vector, it encoded a gene for nerve growth factor, the construct was administered via stereotactic injection, it only tested pre-clinically and rodents, it was given at a dose of one times 10 sixBG per patient, the viral serotype was chosen for its ability to cross the blood brain barrier