If a motor is sound-insulated, then it is quiet enough to use in home appliances. ... ...

If a motor is sound-insulated, then it is quiet enough to use in home appliances. If a motor is quiet enough to use in home appliances, then it can be used in institutional settings. None of the motors manufactured by EM Industries are quiet enough to use in home appliances. If the statements above are true, which one of the following must be true?
(A)  If a motor can be used in institutional settings, then it is sound-insulated. 

(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in PT71 (Dec 2013): Logical Reasoning A