What are the desirable traits for which variety improvement is done in poultry?
Your question does not indicate if the variety improvement is for crops or livestock.
Here are some links that might be helpful:
https://www.meritnation.com/ask-answer/question/the-factors-for-which-variety-improvement-is-done/improvement-in-food-resources/7501595
https://www.meritnation.com/ask-answer/question/explain-any-four-desirable-traits-for-which-variety-improvem/improvement-in-food-resources/9237941
If this is not helpful, kindly post the complete question again.
Here are some links that might be helpful:
https://www.meritnation.com/ask-answer/question/the-factors-for-which-variety-improvement-is-done/improvement-in-food-resources/7501595
https://www.meritnation.com/ask-answer/question/explain-any-four-desirable-traits-for-which-variety-improvem/improvement-in-food-resources/9237941
If this is not helpful, kindly post the complete question again.