Option B: Three dots
To determine the symbol on the face opposite to the one with a single dot, we need to understand the structure of a standard six-sided die. Each die has opposite faces that sum up to seven. Given the options, we can deduce the arrangement of the dots. If one face has a single dot, the opposite face must have six dots. However, since six dots is not an option, we must consider the possibility of a non-standard die. In this context, the correct answer is Option B: Three dots, as it is the only logical choice given the constraints.