If I showed you a picture of a green surface, and asked you what color it is, would you say that it’s white and that there’s probably green light shining on it?
No, but it doesn’t mean the other answer is invalid too. If there is no reference in the picture to tell what kind of light condition it was shot at, both answers could be possible.
So if we’re just going by what’s possible then the wall could be yellow and have a blue light, or it could be white with one yellow and one blue light.
If I showed you a picture of a green surface, and asked you what color it is, would you say that it’s white and that there’s probably green light shining on it?
No, but it doesn’t mean the other answer is invalid too. If there is no reference in the picture to tell what kind of light condition it was shot at, both answers could be possible.
So if we’re just going by what’s possible then the wall could be yellow and have a blue light, or it could be white with one yellow and one blue light.