Assuming 100% ionisation which will have maximum pH?

Due to hydrolysis of NH4+ion, solution is acidic. NH4​Cl is salt of NH4​OH and HCl so it dissociates to give only one H+ ion.(NH4​)2​SO4​ is salt of NH4​OH and H2​SO4​ so it dissociates to give only two H+ ions.(NH4​)3​PO4​ is salt of NH4​OH and H3​PO4​ so it dissociates to give only three H+ ion. So it has maximum PH