Which day of the week fell on 1 January 1911?

Correct answer: Option A — Sunday. Counting total odd days up to this date, or using a verified Gregorian calendar calculation, gives weekday index 6 where Monday is 0; therefore the day is Sunday. Option B (Monday) is rejected because it does not equal the computed result; it represents a counting, direction, leap-year, interval, or hand-motion error. Option C (Tuesday) is rejected because it does not equal the computed result; it represents a counting, direction, leap-year, interval, or hand-motion error. Option D (Thursday) is rejected because it does not equal the computed result; it represents a counting, direction, leap-year, interval, or hand-motion error.