Final answer:
The line is from "Dulce et Decorum Est" by Wilfred Owen, a poem that offers a vivid portrayal of World War I and critiques the romanticization of war.
The answer is option ⇒ a) "Dulce et Decorum Est"
Step-by-step explanation:
The line "Till on the haunting flares we turned our backs" is from the war poem "Dulce et Decorum Est" by Wilfred Owen. This poem is renowned for its harrowing depiction of the gas attacks during World War I and its stark criticism of the romanticization of war.
It is one of Owen's most famous works and is known for its vivid imagery and sharp critique of the idea conveyed by the Latin phrase dulce et decorum est pro patria mori, which translates to 'it is sweet and honorable to die for one's country'.
The answer is option ⇒ a) "Dulce et Decorum Est"