An alloy is a combination of

An alloy is a homogenous mixture because its composition is uniform.

A homogeneous mixture is one in which the composition is uniform throughout the solution. 

All of the components in a homogeneous mixture are evenly distributed, and in the soft drink, we find sugar, carbon dioxide, and water forming a single phase. As a result, a soft drink is a uniform mixture.

Hence, the correct option is 3.