Which factors protected russia from control by napoleons army? whats the answer

The factor that protected the Russia from control by Napoleons army was their constant retreating policy which never let Napolean have a full fledged war. napoleaon had prepared with all required stocks to fight the Russians in a full fledged battle, but the Russians cleverly played a hit and run game. The Russians cleverly draged the war for long to make Napoleaon frustrated. The Russians slowly dragged the war to the Harsh winter season although the war started in the spring season. Russia was a large country and protecting the backlines with soldiers became very hard with each passing day.

The answer to the question is moraine