Explanation

M. Najeeb Haroon is the correct answer because he was reported to have paid the highest tax among parliamentarians in 2019. M yaqoob Shaikh is incorrect as this information does not confirm him as the highest payer. Saleh Muhammad is incorrect because there is no evidence provided that he paid the most tax. Shaukat Ali is incorrect because he did not pay the highest amount compared to M. Najeeb Haroon.