Which of the following is true?

a) only primary reinforcers trigger dopamine release in the ventral tegmental area/substantia nigra pars compacta

b) amimals will continue to work for electrical brain stimulation if dopamine transmission is blocked

c) dopamine seems to be involved in liking rather than wanting a reinforcer

d) a trained animal will reduce its response rate if dopamine transmission is blocked

(d)

Explanation:

A trained animal will reduce its response rate if dopamine transmission is blocked.

Dopamine is a happy hormone released during many conditions including falling in love with some one, liking someone etc. Dopamine develop likeliness towards opponent partner to mate and reproduce. Further this hormone help animals to responds happily towards special stimuli. So if this hormone stop secreting it results in late repose or no response towards a particular stimuli.

they deliver oxygen to the blood

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.