To solve this question, the user needs to know the definitions of the given options and be able to identify the option that describes a person who does something for love, not money.
A. agnostic: a person who believes that it is impossible to know whether or not God exists.
B. amateur: a person who engages in a pursuit, especially a sport, on an unpaid basis.
C. ambidextrous: able to use both hands equally well.
D. autotoxin: a toxin produced by an organism that acts upon its own tissues or cells.
Option B, amateur, is the correct answer because it describes a person who does something for love, not money. An amateur engages in a pursuit, especially a sport, on an unpaid basis. Options A, C, and D are incorrect because they do not describe a person who does something for love, not money.
The Answer is: B. amateur