As I see it, only group B is a metaphor. To say that "it cast a different light on the situation" (metaphorically) means that our perspective has changed, and ultimately our opinion or the way it was formed.
When looking at a scene, everything depends on the lighting, so when we "see it in a different light" we are considering different reasons or factors than the 'standard' or the way we saw it before.
Say I saw a sunlit scene of a man smiling warmly in the sunlight (a sunny disposition). Now I find out that that man is a murderer. I will no longer find his complexion sunny. I would see him in a 'manic' 'twisted' 'cold' or somesuch light, as if the sky had become somehow ligted differently in order to show his bad qualities in my perception.
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