Normality (N) is defined as the number of gram equivalents of solute per litre of solution. For an acid, the number of equivalents equals the number of moles multiplied by the number of replaceable hydrogen ions (n-factor). For H₂SO₄, n-factor = 2 (diprotic acid). First, find the new molarity after dilution using M₁V₁ = M₂V₂: 2 M × 50 mL = M₂ × 200 mL, so M₂ = 100/200 = 0.5 M. Normality = Molarity × n-factor = 0.5 × 2 = 1.0 N. Option 0.5 N would be correct if H₂SO₄ were monoprotic (n = 1). Option 2.0 N corresponds to the normality before dilution (2 M × 2 = 4 N) or an incorrect dilution calculation. Option 4.0 N is the normality of the original undiluted 2 M H₂SO₄ solution, forgetting the dilution step. The relationship N = M × n-factor is a key inter-conversion in NCERT volumetric analysis and is extensively tested in JEE Main's analytical chemistry section. Plausibility check: dilution must reduce both molarity and normality proportionally; 0.5 M × 2 = 1.0 N is dimensionally and numerically consistent.