What is the minimum speed limit on state highways?

Answer: C — 35 mph

The other options are not the minimum speed limit on state highways because they either exceed the minimum limit or are below it. Option A and B are more suitable for residential areas due to lower traffic speeds, while Option D is closer to the maximum speed limit on most state highways, which is usually 55 mph. Option C is the most reasonable and commonly enforced minimum speed limit on state highways.