Which two digits are swapped to transform 6789 into 8769?

• A. Hundreds and Units Digits
• B. Tens and Units Digits
• C. Thousands and Tens Digits
• D. Thousands and Hundreds Digits

Answer: (C)

Swapping digits means exchanging which values sit in two positions of the number. In 6789, the digits occupy thousands, hundreds, tens, and units. If we swap the thousands place digit (6) with the tens place digit (8), the leftmost digit becomes 8 and the tens digit becomes 6, while the others stay the same, giving 8769. The hundreds and units digits stay as 7 and 9, so this is the only swap that produces 8769.