IMHO, A is wrong because of how strong it is. What makes it strong is the usage of “will have to”. The literal meaning of A basically says that unless we solve this problem, employees do not have any other choice but to encrypt the texts. If it used something like “might have to” there would be more potential for this to be the correct answer. Author also hinted that it is inconvenient practice at the end of the passage, which can be further inferred that not everyone will practice encrypting their messages. Avoid strong terms on conclusion/main point questions unless there is same strength present in the passage (happens pretty rarely).

I think you are confusing “folklorists” with “people who transmitted folklore”. It is not the same thing.

If performers had no creative role (as A says) - that’s what folklorists/folklore studies believed/concentrated on and it is a proper inference, because “since the early 1970s, folklore studies have begun to regard folk performers as people of creativity”.

they must’ve been unaware of it (as B says). - we can not infer whether performers are aware or not , since we are told nothing about the way they think of themselves/their position. We are only told about the way they were perceived in the eyes of folklorists/folklore studies.

You got this!!!!