Answer: Cause related marketing
Explanation: In simple words, it refers to a marketing strategy in which an organisation sets its promotional campaign in such a way that it serves for the purpose of betterment of society along with creating brand awareness among individuals.
In the given case, Martin is marketing their product with the message that the a part of their revenue will go to charity foundation. Hence they are serving the dual purpose
Thus, from the above we can conclude that the correct option is B.