I believe the compound is Phosphorus pentoxide
The answer is D: A metal is added to an acid and hydrogen gas is formed, because that's a chemical reaction
Freidal craft reaction is the attack of a carbon or carbon chain on aromatic ring with the help of anhydrous AlCl3 to produce alkylated benzene ring.
Only ketone not be able to undergo friedal craft reaction as, it is not aromatic compound whereas all the given reactants are aromatic and gives friedal craft reaction.
If I understand you correctly, then this is the equation for the breakdown of monosaccharide.
monosaccharide --> Carbon dioxide + water