Odd man out:mercury,gold,br,silver.…

None of the candidates are men! It is a stupid (poor) question. Part of being a successful student though is guessing what the 'desired' answer is and if the 'correct' answer was given in reading ignments or lectures you have to take your lumps. Every oriental rug (I am told) has a tiny defect (on purpose) such as a slight non-symmetry on opposite corners (because only Allah is perfect). Life is like that. BTW, mercury is the only toxic substance on the list (odd man out for wrong reason?). They say that when a little boy bit a thermometer it was a chilly day the day the mercury went down!