Assertion :Sulphide ores are concentrated by froth flotation process. Reason: Pine oil forms emulsions in water.
The single most important operation used for the recovery and upgrading of sulphide ore. Only sulphide ores are concentrated by froth flotation process because pine oil selectively wets the sulphide ore and hence brings it to the froth. The sulphide ores preferably wetted by the oil and the gangue with the water. Hence A is answer.