With no explanation, label text_A→text_B with either "DON'T KNOW", "NO" or "YES".
text_A: With Robert J. Flaherty's "Nanook of the North" in 1922, documentary film embraced romanticism; Flaherty filmed a number of heavily staged romantic films during this time period, often showing how his subjects would have lived 100 years earlier and not how they lived right then. Despite this, in "Nanook of the North", Flaherty encouraged his subjects to shoot a walrus with a nearby shotgun, rather than use a harpoon instead. Some of Flaherty's staging, such as building a roofless igloo for interior shots, was done to accommodate the filming technology of the time.
text_B: Did Flaherty's subjects shoot a walrus with a harpoon?
NO.