Did you mean mechanical ? If you do mean mechanical then here's the answer to your question:
Mechanical digestion is when the food is being broken down physically into smaller pieces from the mouth and chemical digestion is when the food is being broken down into substance particals starting from the saliva and proceeding through the small intestines.
The answer is the last option because HIV is different in every person. HIV mostly never has visible signs so a blood test will be the best choice. Hope this helps!!
