Which Is the More Appropriate Statement: Opioids Have Endorphin Activity

Which is the more appropriate statement: Opioids have endorphin activity, or endorphins have opioid activity? Explain your answer.

A) Opioids have endorphin activity because endorphins likely came first.
B) Endorphins have opioid activity because opioids likely came first.
C) Opioids have endorphin activity because plants likely created opioids to mimic their own endorphin systems.
D) Endorphins have opioid activity because plants likely created opioids to mimic their own endorphin systems.