Yes, the roots are usually the organ for feeding.Just in insectivorous plants (sundress, pitcher plants, butternut's, bladderworts, Venus's-flytrap etc.) the main organs for feeding are leaves.Sometimes we say "the organs for feeding is the leave" this statement may be correct but in scientific terms and in most plants the organ for feeding is the root.In the cactus plant which is usually found in deserts (Sahara desert etc.) the main feeding organs are 1) The stem and 2) RootsBut For The Conclusion:-ROOTS ARE THE MAIN FEEDING ORGANS OF THE PLANTIN VERY LESS PLANTS SUCH AS CARNIVOROUS AND CACTUS PLANTS THE FEEDING ORGANS MAY BE OTHER(The Wrong Answer)(The Correct Answer)