What is the recommended procedure for changing the transmission fluid in a vehicle?
a. Locate the transmission fluid drain plug, remove it to drain the old fluid, replace the drain plug, and then refill the transmission with new fluid through the fill port.
b. Remove the transmission pan, clean it, replace the filter, and then refill the transmission with new fluid through the drain plug.
c. Drain the engine oil, remove the transmission, clean it, and then refill it with new transmission fluid.
d. Add new transmission fluid directly into the engine oil fill port to ensure it circulates through the transmission system.