Task: Explanation
Input (English): Porsche has been successful in many branches of motorsport of which most have been in long distance races. Question: Günter "Bobby" Klass was a factory driver for a company that has been successful in many branches of motorsport of which most have been in what? Answer: long distance races
Output (English): Porsche has been successful in many branches of motorsport of which most have been in long distance races.