What distinguishes a ratio scale from an interval scale?

A ratio scale is distinguished from an interval scale primarily by the presence of a true zero point. This true zero means that a value of zero on a ratio scale indicates the absence of the quantity being measured, allowing for meaningful comparisons of magnitudes. For example, in a ratio scale measuring weight, a weight of zero means there is no weight at all, which is not the case with interval scales.

In contrast, an interval scale has equal intervals between values but does not have a true zero point. For example, temperature measured in Celsius has a zero point, but it does not mean 'no temperature'; rather, it is an arbitrary point on the scale. This fundamental difference allows ratio scales to support operations such as multiplication and division, which are not meaningful with interval scales.

The other options do not capture the key distinction effectively. Non-numerical values refer to categorical scales rather than interval or ratio, averages can be calculated with both scales, and the degree of measurement accuracy is not a criterion that differentiates between these two types of scales in the context of their definitions and applications.