That would be A. Photosynthesis.
Based on the diathesis-stress model schizophrenia is the result of interaction between environmental and biological/genetic factors. According to this model, when the combination of the predisposition (diathesis) and the stress (biological, social, and psychological stressors) exceeds a threshold, the person will develop a disorder.
When the continents are at the Earths poles, they receive less sunlight.
