Answer:
(c) only solute present
Step-by-step explanation:
In chemistry, the mole fraction, denoted by X, refers to the number of moles of a substance in a compound/mixture divided by the total number of substances in the same compound or mixture.
In this case, we can say that mole fraction represents the number of solutes to the number of solutes and solvent in the solution i.e. X = nA/nA + nB
Where; nA = number of solutes
nB = number of solvent
X = mole fraction.
Based on this analogy, When the mole fraction of solute is 1, there is only solute present. That is; X = 1 / 1 + 0
X = 1/1 = 1.