On which weekday did March 31, 1927 occur?

Correct answer: Option C — Thursday. Counting total odd days up to this date, or using a verified Gregorian calendar calculation, gives weekday index 3 where Monday is 0; therefore the day is Thursday. Option A (Friday) is rejected because it does not equal the computed result; it represents a counting, direction, leap-year, interval, or hand-motion error. Option B (Saturday) is rejected because it does not equal the computed result; it represents a counting, direction, leap-year, interval, or hand-motion error. Option D (Monday) is rejected because it does not equal the computed result; it represents a counting, direction, leap-year, interval, or hand-motion error.