Which three components are common to all amino acids? a. an amino group, a carboxyl group, and an r group b. an amino group, a phosphate group, and an r group c. a five-carbon sugar, a phosphate group, and a nitrogenous base d. a five-carbon sugar, an amino group, and a nitrogenous base

The correct answer is A.  an amino group, a carboxyl group, and an R group

An amino acid is a unit or building block of a protein. There are 20 different types of amino acids present and all amino acids composed of five basic parts. These are a central carbon (C) atom, a hydrogen(H) atom, an amino group (NH₂) having one nitrogen atom and two hydrogen atoms, a carboxyl group (COOH) having one carbon atom, two oxygen atoms, and one hydrogen atom and a R-group or side chain.