Answer: Both produce energy.
Explanation: Both provide each other with the necessary ingredients for the process to take place: glucose and oxygen for cellular respiration, carbon dioxide and water for photosynthesis.
The biological basis for assigning all human beings into a singe species is that there so many, even tons of living organisms living on earth. These organisms differ in their external and internal organs and so to differentiate them from them, they are being classified into kingdoms then classes then phylums then family.
C is the proper answer. They have been reduced by using unleaded gasoline because lead can harm the air and water we breathe, so using less of it will help reduce the pollution being caused by it.