Which statement about PET scanning is correct?
A. A positron is emitted by the radiotracer that interacts with an electron in the detector producing two γ-rays that move apart at 180° to each other.
B. A positron is emitted by the radiotracer that interacts with an electron in the detector producing two γ-rays that move apart at right angles to each other.
C. A positron is emitted by the radiotracer that interacts with an electron in the surrounding tissue producing two γ-rays that move apart at 180° to each other.
D. A positron is emitted by the radiotracer that interacts with an electron in the surrounding tissue producing two γ-rays that move apart at right angles to each other.