The correct option is A Chitosan
Starch-based bioplastics are often blended with biodegradable polyesters to produce starch / polycaprolactone or starch/Ecoflex. In this biopolymer, nanoparticles are the functional parts of the technology as they remove calcium and magnesium components of water through ion exchange. Thus, it shows the same process that is used by common water purifiers