Classify the year 1600 correctly according to the Gregorian leap-year rule.

Correct answer: Option A — Leap year. 1600 is divisible by 4. Hence it is a leap year. Option B (Ordinary year) is rejected because it does not equal the computed result; it represents a counting, direction, leap-year, interval, or hand-motion error. Option C (Century year only) is rejected because it does not equal the computed result; it represents a counting, direction, leap-year, interval, or hand-motion error. Option D (Cannot be determined) is rejected because it does not equal the computed result; it represents a counting, direction, leap-year, interval, or hand-motion error.