The correct answer to this question is A. A solution is a mixture made up of at least substances, and usually it is hard to separate the two after the solution is mixed. A solution is two components: a solvent and a solute.
The solvent is the mixture that makes up the majority of the solution and is the component that dissolves the other substance(s). The solute is the component that is introduced. Water is a common solvent. In this question, the sugar is introduced to the iced tea, making sugar the solute and the iced tea the solvent.