Determine Which of the Lettered Claims Below Is Equivalent to the Following:If

Short Answer

Determine which of the lettered claims below is equivalent to the following:If the gun cannot be sold,then it does have a trigger lock.(This can be easy to do if you symbolize the claims first and have some familiarity either with truth tables or with the Group II rules for derivations-the truth-functional equivalences. )
A.Only if the gun has a trigger lock can it be sold.
B.The gun has no trigger lock,but it can be sold anyway.
C.If the gun cannot be sold,then it has no trigger lock.
D.If the gun has no trigger lock,then it can be sold.
Equivalent to D