When Andrew Buys Purple Boxer Shorts at Nia's Store for $20

Multiple Choice

When Andrew buys purple boxer shorts at Nia's store for $20,

A) Andrew's marginal benefits must be at least $20.
B) Nia's marginal opportunity costs must greater than $20.
C) Nia's marginal benefits from the $20 must be less than from the boxer shorts.
D) Andrew's marginal opportunity costs must be greater than $20.
E) this is an involuntary exchange because Andrew wouldn't be caught dead in purple boxer shorts.