Final answer:
Tim's decision to not attend the protest due to rain is a social problem, specifically a collective action problem, as he anticipates others will also be deterred from participating.
Step-by-step explanation:
The type of problem being described where Tim decides not to go to the protest because of the rain is a social problem. The problem stems from a phenomenon known as the collective action problem, where individuals have a disincentive to participate in an action because they expect others to be deterred by the factors such as bad weather. In this case, Tim assumes that because it's unpleasant to be outside in the rain, other individuals will also choose not to go to the protest, reducing its effectiveness and making his own participation seem less valuable thus he decides against going.