When two people voluntarily trade with each other:
a. one person will be better off and the other person will be worse off.
b. whether they will be better off or worse off depends on how they negotiate with each other.
c. both of them will be worse off.
d. both of them will be better off.

D. Both of them will be better off.

Explanation:

In the voluntarily trade is a fair trade and in it both parties will finish being better off, meaning they will trade what they do not need for the thing they do need and that will help them off. Volunteer trade implies that no one is forced into labor or trade and that they had the freedom to sell or buy goods or services under their own terms.

In case one or both sides of the trade are damaged, the trade can't be considered volunteered or fair.

1) why is this social studies?

and

2) don't do that anympore?

xd