A)Proteoglycans can act as filters to regulate which molecules pass through the extracellular medium. B)The negative charge associated with proteoglycans attracts cations, which cause water to be sucked into the extracellular matrix. C)Proteoglycans are a major component of compact connective tissues but are relatively unimportant in watery tissues such as the jellylike substance in the interior of the eye. D)Glycosaminoglycans are components of proteoglycan.