Due to a law being a predicted sort of event that is bound to happen every time, a pattern, we can say that since the cell theory is a pattern instead of a possible explanation, it can be a law. However, since we don't have an accurate explanation to the part which claims that they all come from pre-existing cells, it is a theory, we don't have enough information to confirm that the theory is a solid fact, therefore, we can't confirm that it is a law.
I think the correct answer from the choices listed above is option C. The function that is both performed by goblet cells and lacrimal glands is protection. They produce mucus in order to protect mucous membranes. Hope this answers the question.
