Maximum Number of Active Hydrogens in Different Compounds

Acetic Acid (CH3COOH)
- Acetic acid has a chemical formula of CH3COOH.
- The carbon atom in the carboxyl group (COOH) is bonded to two oxygen atoms and has one hydrogen atom directly attached to it.
- The other carbon atom in the compound is bonded to three hydrogen atoms.
- Thus, acetic acid has a total of 4 active hydrogens: one from the carboxyl group and three from the methyl group.

Methane (CH4)
- Methane has a chemical formula of CH4.
- It consists of a single carbon atom bonded to four hydrogen atoms.
- All four hydrogen atoms in methane are directly attached to the carbon atom.
- Thus, methane has a total of 4 active hydrogens.

Glycerol (C3H8O3)
- Glycerol, also known as glycerin, has a chemical formula of C3H8O3.
- It consists of a chain of three carbon atoms, each bonded to two hydrogen atoms.
- One of the carbon atoms is also bonded to an oxygen atom, which forms a hydroxyl group (-OH).
- Glycerol has a total of 3 hydroxyl groups.
- Each hydroxyl group has one active hydrogen.
- Thus, glycerol has a total of 3 active hydrogens.

Methanol (CH3OH)
- Methanol has a chemical formula of CH3OH.
- It consists of a carbon atom bonded to three hydrogen atoms and one oxygen atom.
- The oxygen atom forms a hydroxyl group (-OH) with the carbon atom.
- The hydroxyl group has one active hydrogen.
- Additionally, the carbon atom is also bonded to three hydrogen atoms.
- Thus, methanol has a total of 4 active hydrogens.

Conclusion
- Among the given compounds, glycerol has the maximum number of active hydrogens with 3, followed by acetic acid and methanol with 4 each, and methane with 4 as well.
- Therefore, the correct answer is option 'C', glycerol.