Option 1 -> Lump-sum Taxes are fixed amount taxes that remain constant regardless of income level.
Option 2 -> Proportional Taxes maintain a constant tax rate, but the amount paid still varies with income.
Option 3 -> Non-income Taxes is a broad term but not the specific technical term used in economics.
Option 4 -> Service Taxes are levied on services and may or may not depend on income.
Hence, Lump-sum Taxes -> Lump-sum taxes are fixed taxes that do not vary with income, consumption, or any other economic variable. Every taxpayer pays the same fixed amount regardless of their income level. In economic theory, lump-sum taxes are considered non-distortionary because they do not affect economic decisions or behavior, making them efficient from a theoretical standpoint, though they may raise equity concerns in practice -> correct