The correct answer is B. False.
A rational agent is one that acts in its own best interests. This does not mean that a rational agent will always do the right thing, as what is in the best interests of an agent may not always be what is right. For example, a rational agent may steal if it believes that it will benefit from doing so, even though stealing is wrong.
On the other hand, a person who always does the right thing may not be acting rationally. For example, a person who gives away all of their money to charity may be acting in a way that is morally right, but it may not be in their own best interests.
In conclusion, a rational agent is not necessarily one who always does the right thing, and a person who always does the right thing may not be acting rationally.