The climax of Nectar in a Sieve occurs when . Irawaddy resorts to prostitution and bears an albino child
Rukmani and Nathan have to move to the city to live with their son
Kenny begins construction on the new hospital where he and Selvam will work
Rukmani and Nathan find out that their son is missing and cannot be found

The climax of a plot is the major turning point that allows the protagonist to resolve the conflict. The end of Part I brings the climax of the novel - after years of struggling against nature and the tannery, Ruku and Nathan lose the battle and their land. Unable to pay the land dues, they are forced to leave the only way of life they’ve ever known. This greatest change brings Ruku her greatest challenge yet; because Nathan is old and unable to get employment elsewhere, they must travel to the city to find and live with their son Murugan.

Explanation:

black citizens were denied access to the same public facilities as whitesun.

marriages between white and nonwhite citizens were forbidden.

nonwhite citizens were required to carry identification papers with them at all times.