The farmers cell has be initiating its susceptibility towards the pesticides. The farmer if continues working in the field then he will develop the disease.
This susceptibility has developed because the cell has been in long term exposure to the pesticides as he works in the field.
The cells of the body lacks natural and fresh environment which is replaced with dirty and pesticides.
Yes, Mary did make the right choice because Jason was being rude towards a Pt(patient) and Mary talked to him privately about it and he felt the need to get mad and yell at her so she did the right thing of telling the manager