Final answer:
Mustard gas was a lethal chemical weapon used in WWI that caused skin and lung blisters, blindness, and death, with symptoms taking hours to days to manifest. So, correct option is (c).
Step-by-step explanation:
The effects of mustard gas during World War I were devastating and long-lasting. Mustard gas was a chemical weapon used in trench warfare that could cause severe blisters on the skin and in the lungs, potentially leading to blindness, lifelong respiratory problems, and even death. The gas took about 24 hours to manifest its effects, which could last for weeks, and its victims endured a slow and painful struggle.
Combined with other gases like chlorine and phosgene, chemical warfare added to the horrors of the trenches and the overall misery of the war without significantly changing its outcome. While mustard gas poisoning took an excruciating 24 hours to begin and possibly up to five weeks to result in death, phosgene gas was often fatal more rapidly, though its symptoms might not be immediate.
Gas attacks were feared by soldiers as the gas settled into trenches and could cause injuries even before being noticed, making it one of the war's most dreaded aspects. The development and use of poison gas during the war symbolized the extreme measures taken by nations involved, resulting in misery for combatants and civilians alike. In response to the horrific effects of such weapons, chemical warfare was banned under the Geneva Protocol in 1925.