D.) There must be an equal number of atoms of each element on both sides of the equation
The main function is to help them see with all their eyes.
Explanation:
The structures of both acetone and propanal are shown below:
In the formula of propanal there is -CHO functional group at the end.
In acetone -CO- group is present in the middle that is on the second carbon.
The molecular formula is C3H6O.
Both have same molecular formula but different structural formulas.
I’m pretty sure the answer is “plant cell”