The sample space for the spinner consists of the outcomes 1, 2, and 3.
If the spinner is evenly divided into three sections corresponding to the numbers, then all outcomes (1, 2, and 3) would be equally likely, assuming the spinner is fair. If the sections are of different sizes or the spinner is biased in some way, then the likelihood of each outcome would differ. But with no additional information suggesting any bias, the assumption is that all outcomes are equally likely.