The answer would be A. value
The reason is quite simple: because of the necessity of the plot completing the main character’s arc by an act of redemption, which is one of the main themes of the novel.
Indeed, Amir does not really need to return to Afghanistan, he lives a successful and happy life in the USA as a novelist, yet he is lacking something important which compels him emotionally and psychologically to go back to a dangerous, war-torn country. That something is redemption which is proven by the sentence Hassan’s father utters when he contacts him: "There is a way to be good again."
And that way is to save Sohrab, Hassan’s son from both the Taliban regime and Assef, the child predator. Hassan is dead because he is the symbol of a wound that can never be fully closed. What Amir did to him was unforgivable and has haunted him for years. Sohrab is a second chance for Amir to do the right thing he failed to do when he was a child and to finally be brave and risk his life for a good cause. Assef is the symbol of the past that is always present to Amir through his guilt.
Their final encounter mirrors the past in that Amir finally stands up to Assef how he should have in the past and by doing that he redeems himself and is yet again saved by Hassan in the form of his son Sohrab who fulfills the promise (or even prophecy) that Hassan had made to Assef, that he would use his slingshot to shout out his eye with it. In this manner, the character arc and the plot reach their conclusion.
It develops in the uterus during pregnancy so it’s true
Global warming
Rising global temperatures caused by CO2 emissions heat the water, reducing its oxygen content.
Deforestation
Felling forests can exhaust water resources and generate organic residue which becomes a breeding ground for harmful bacteria.
Industry, agriculture and livestock farming
Chemical dumping from these sectors is one of the main causes of eutrophication of water.
Rubbish and faecal water dumping
The UN says that more than 80% of the world's sewage finds its way into seas and rivers untreated.
Maritime traffic
Much of the plastic pollution in the ocean comes from fishing boats, tankers and cargo shipping.
Fuel spillages
The transportation and storage of oil and its derivatives is subject to leakage that pollutes our water resources.
EFFECTS OF WATER POLLUTION
Deteriorating water quality is damaging the environment, health conditions and the global economy. The president of the World Bank, David Malpass, warns of the economic impact: "Deteriorating water quality is stalling economic growth and exacerbating poverty in many countries". The explanation is that, when biological oxygen demand — the indicator that measures the organic pollution found in water — exceeds a certain threshold, the growth in the Gross Domestic Product (GDP) of the regions within the associated water basins falls by a third. In addition, here are some of the other consequences:
Destruction of biodiversity. Water pollution depletes aquatic ecosystems and triggers unbridled proliferation of phytoplankton in lakes — eutrophication —.
Contamination of the food chain. Fishing in polluted waters and the use of waste water for livestock farming and agriculture can introduce toxins into foods which are harmful to our health when eaten.
Lack of potable water. The UN says that billions of people around the world have no access to clean water to drink or sanitation, particularly in rural areas.
Disease. The WHO estimates that about 2 billion people have no option but to drink water contaminated by excrement, exposing them to diseases such as cholera, hepatitis A and dysentery.
Infant mortality. According to the UN, diarrhoeal diseases linked to lack of hygiene cause the death of about 1,000 children a day worldwide.
