I'm having a hard time understanding why B is the right answer and not E.
Both passages state that their fields are not effectively covered by current IP law and so I feel that answers B because it gives a reason why individuals in those fields wouldn't rely on legal protections.
Passage B also states that trade secrecy laws are potentially available and are seldom used but doesn't give an explanation. While that is true, it is immediately preceded by the challenges chefs face in IP battles. And so, I feel that those are good reasons why chefs would choose not to engage.
In defense of choice E, passage A explains the sanctions that occur when individuals don't follow the social norms but Passage B does not. Passage B does not at all discuss what is prohibitive about the social norms in place. It explains what chefs do but doesn't explain why anyone follows the rules, it doesn't explain the prohibitive nature of the rule system.
So, I'm having a tough time seeing how choice B goes unanswered by Passage B while E is.