Option (B) 276
Required number = HCF(281 − 5, 1249 − 7) = HCF(276, 1242).
276 = 2² × 3 × 23; 1242 = 2 × 3³ × 23. HCF = 2 × 3 × 23 = 138.
Correct answer: C) 138
Subtract each remainder from the respective number to get values exactly divisible by the required HCF: 281 − 5 = 276 and 1249 − 7 = 1242. The greatest such divisor is HCF(276, 1242) = 138. A common mistake is stopping at 276 (option B) without computing the actual HCF.