Placebo pills and acupuncture have both been effective in reducing pain. the common element in both of these methods may be their ability to stimulate the

Answer

               Placebo pills and acupuncture have both been effective in reducing pain. the common element in both of these methods may be their ability to stimulate the release of endorphins.

this is the commonality between placebo pills and acupuncture.

the supermassive black hole is in the middle of the galaxy.

it is either c or d and i know for sure it is not a or b