Option 1 -> Incorrect. This includes (B) which is not a demerit of price ceiling.
Option 2 -> Incorrect. This includes (B) which is not a demerit of price ceiling.
Option 3 -> Incorrect. This includes (B) which is not a demerit but rather the opposite occurs under price ceiling.
Option 4 -> Correct. This correctly identifies only the actual demerits.
Hence, Option 4: (A), (C) and (D) only -> Price ceiling creates several demerits: (A) Black Marketing emerges because artificially low prices create shortages, encouraging illegal sales at higher prices; (C) Low quality products result as producers cut costs to maintain margins under controlled prices; (D) Long queues occur due to excess demand over supply, requiring rationing systems. However, (B) Stability of income of producers is NOT a demerit - in fact, price ceilings cause instability and reduction in producer income, which is the actual demerit. Statement (B) as written describes something positive, not a demerit. -> correct