Which of the Following Is True About Absolute Advantage Principle

Which of the following is true about absolute advantage principle?

A) According to this approach, enhanced product specialization adversely affects communal welfare.
B) This approach allows the nation to consume more than it otherwise could, generally at lower cost.
C) This is the only approach that can be used to explain why nations attempt to run a trade surplus.
D) This approach explains the process by which firms acquire and retain one or more value-chain activities inside the firm.