Following order of operations (PEMDAS/BODMAS), multiply first: 5*5 = 25, then add: 25+6 = 31, which is option B. Option A (55) incorrectly treats this as concatenation. Option C (16) incorrectly does 5*5=25, then 2+5=7, then 7+6=13 (not 16 anyway). Option D is nonsensical.