A picture of a patient’s lung showed it to be shriveled and darker than usual.Which is most likely the cause of this lung condition?

Smoking is the most likely cause. Chemicals in tobacco smoke damage lung tissue and can cause chronic lung disease, making the lungs appear darker and less healthy. Overeating and poor refrigeration do not directly cause this kind of lung damage, and sickle cell anemia primarily affects red blood cells and blood flow.

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