In Separate Investigations,Robert Heath and Olds and Milner Demonstrated That

In separate investigations,Robert Heath and Olds and Milner demonstrated that

A) electrical stimulation of the brain has no apparent behavioral effects.
B) animals and people will self-administer electrical stimulation to certain parts of the brain.
C) animals,but not humans,respond positively to electrical stimulation applied to certain parts of the brain.
D) surgically implanting stimulating electrodes in animals and people usually results in coma or death.