The prefix 'mono-' in the term 'monoclonal antibody' most directly indicates which of the following?

That each antibody molecule binds to only one type of antigen without any potential for cross-reactivity with related epitopes or antigens in complex biological environments, thereby ensuring absolute exclusivity of binding under all physiological conditions.

That antibodies are produced from a single serum donor rather than pooled sera from multiple sources.

That the antibody is monovalent (can bind only one antigen molecule), as opposed to bivalent or polyvalent forms.

That the antibody population originates from a single B-cell clone producing identical antigen-binding sites.