1every 30,000 miles, replace the brakes vacuum the interior service the automatic transmission (if your car has one) inspect the trunk latch

It is recommended to change or service the automatic transmission fluid for every 30,000 miles. This is the ideal schedule for the average driver and will allow your transmission to run on well fluid continuously, which ultimately means a longer lasting and more efficient transmission. Even though there isn’t any damage in regular fluid changes, they recommend getting it changed every 30,000 to 60,000 miles for better outcomes on your transmission. But there are circumstances where a fluid change should be done sooner, and it will all rest on on your driving routines and other various factors. If you see to do some heavy towing, carrying, common stop-and-go driving, live in a very hot climate, or snow plowing, you should ponder getting your fluid changed sooner, perhaps every 15,000 miles 

The answer is d) by requesting advice on science internet sites