What does "this" refer to? CHOOSE the idea that completes the sentence

Read the excerpt from elie wiesel’s all rivers run to the sea. why were those trains allowed to roll unhindered into poland? why were the tracks leading to birkenau never bombed? i have put these questions to american presidents and generals and to high-ranking soviet officers. since moscow and washington knew what the killers were doing in the death camps, why was nothing done at least to slow down their “production”? that not a single allied military aircraft ever tried to destroy the rail lines converging on auschwitz remains an outrageous enigma to me. birkenau was “processing” ten thousand jews a day. stopping a single convoy for a single night—or even for just a few hours—would have prolonged so many lives. based on the paragraph, the author would most likely agree that it is best to avoid confrontation at all costs. people need to be proactive when they witness an injustice. countries should remain neutral to keep alliances strong. moscow and washington are to be blamed for the holocaust.

Question 21 of 25 2 points which sentence is a claim that is both arguable and defensible? o a. giving children mobile phones can protect them in emergencies. b. mobile phones are bad for most individuals, especially children. o c. children should not be given mobile phones, d. mobile phones can be used for good or evil,

Mary cassatt was a trailblazer in the field of impressionist art? a) trueb) false