The "molecule a" referred to ATP in the equation.
So, option A is correct one.
The equation is given as,
[tex]C_{6} H_{12} O_{6}+ 6O_{2}[/tex] → [tex]6CO_{2}+ 6H_{2}O + ATP[/tex]
The above equation indicates the respiration activities in the plants.
The aerobic respiration takes place in the Mitochondria and which requires oxygen and glucose and produces carbon dioxide , water and energy.
The energy is in the form of ATP. The pull form of ATP is adenosine triphosphate. The ATP is also called energy carrier because it found in the cells of the all living organism and this molecule carries energy.
To learn more about aerobic respiration
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