This answer would be A because
Answer:
When you exercise it causes your muscles and your pearl your pures in your skin to produce sweat and cause pain to your nervous system telling you that is exhausting
The answer, I’m pretty sure, is a because more energy is being used to burn which sets off more brightness :)
I don't think they are.
Vascular bundles are strands of tissues, which function as transport system in plants. So they are a kind of tissues, not organs.
diffusion. would be the best answer to use