KEAM 2012 Physics and Chemistry Paper

H3BO3 is a weak Lewis monobasic acid, because it can only accept a pair of electron. None of its hydrogens are ionisable.
Note H3PO3 is a dibasic acid, H3PO4 is a tribasic acid, HNO3 is a strong monobasic acid and H4P2O7 is a tetrabasic acid.