What is the maximum speed limit in California on a rural interstate highway?

Answer: D — 85 mph

In California, the maximum speed limit for rural interstate highways is 85 mph. This may seem like a high speed limit, but it is important to note that this only applies to certain highways, as designated by the California Department of Transportation. Options A, B, and C are incorrect because they are too low compared to the actual speed limit. Option A is the default speed limit for rural highways, option B is the standard speed limit for most highways in California, and option C is the maximum speed limit for some urban freeways with adequate safety measures. Option D is the correct answer as it is the maximum speed limit specifically designated for certain rural interstate highways.