Final answer:
Complexes of IgG bound to soluble multivalent antigens can activate the classical pathway of complement, resulting in complement protein deposition on the complex, targeting it for endocytic uptake by cells bearing complement receptors.
Step-by-step explanation:
When IgG antibodies bind to soluble multivalent antigens, it can activate the classical pathway of complement. Complement activation leads to the deposition of complement proteins on the complex, targeting it for endocytic uptake by cells bearing complement receptors. This process enhances opsonization and promotes rapid clearing of pathogens.