represents amine functional group and 
represents carboxylic acid functional group. When these both functional groups are substituted onto a single carbon atom, then amino acid is formed.
The organic compound consists of functional group and functional group with a side chain is said to be an amino acid.
A: amine group is .
C: carboxylic acid group is
B: amino acid represents functional group and functional group which are substituted onto a single carbon atom.
D: carbohydrate: the general formula of carbohydrate is 
.
Hence, amino acid is the correct answer.
<span>Lithium chloride is LiCl (because the valence of lithium is +1 and the valence of chlorine is -1). So the chemical equation is: Li Cl(s) ----> Li(s) + Cl2 (g). To balance the equation you need to multilply both Li Cl (s) and Li(s) by two, and then you finally get the balanced equation: 2 LiCl ---> 2 Li(s) + Cl2(g). Note that the number 2 to the right of Cl is a subscript.</span>
I guess its D.hope this helps....sorry if i'm wrong.
