Why Did Karl Marx Refer to Religion as the "Opiate

Multiple Choice

Why did Karl Marx refer to religion as the "opiate of the people"?

A) Religion promised people an afterlife in which they would be "high on God"
B) The use of opiates was widespread in religious groups during the industrial revolution
C) Religion was a positive, stabilizing institution for both society and individuals
D) Religion united people under a false sense of common interests and kept them subdued