Who said about the drainage system of Harappan cities that, "it is certainly the most complete ancient system as yet discovered"?

Ernest Mackay

The correct answer is Option (1) → Ernest Mackay

About the drains, Mackay noted: “It is certainly the most complete ancient system as yet discovered.” Every house was connected to the street drains. The main channels were made of bricks set in mortar and were covered with loose bricks that could be removed for cleaning. In some cases, limestone was used for the covers. House drains first emptied into a sump or cesspit into which solid matter settled while waste water flowed out into the street drains. Very long drainage channels were provided at intervals with sumps for cleaning. It is a wonder of archaeology that “little heaps of material, mostly sand, have frequently been found lying alongside drainage channels, which shows … that the debris was not always carted away when the drain was cleared”. FROM ERNEST MACKAY, Early Indus Civilisation, 1948.