Scientists have known for centuries that we "speak" with the left hemisphere of the brain. You perform an experiment in which your subject was presented with an apple only to the left visual field. When asked to identify what he saw, the subject denied seeing anything. However, when asked to point to the correct object, he was able to see and identify the apple. Which reason would explain this deficit?
A) The subject has a brain lesion in the frontal lobes. B) The subject suffered head trauma to the back of his head. C) The subject has a tumor in the left parietal lobe. D) The subject had his corpus callosum severed to control epileptic seizures.