If 1 January 2001 was Monday, what day was it 43 days before?

Correct answer: Option C — Sunday. 43 = 6 complete weeks + 1 days. Moving before by 1 day(s) from Monday gives Sunday. Option A (Monday) is rejected because it does not equal the computed result; it represents a counting, direction, leap-year, interval, or hand-motion error. Option B (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.