Question

How is lung tumor caused?please answer according to grade 6 . Give 4 ways

Answer 1

Smoking causes lung cancer by damaging the cells that line the lungs. When you inhale cigarette smoke, which is full of cancer-causing substances (carcinogens), changes in the lung tissue begin almost immediately.

Answer 2

A lung tumor is the result of abnormal rates of cell division or cell death in lung tissue, or in the airways that lead to the lungs. Types of benign lung tumors include hamartomas and papillomas.There are a number of different kinds of benign lung tumors, such as Hamartoma, and Papilloma.
Caused due to -
1.Smoking
2.Exposure to secondhand smoke. 
3.Exposure to asbestos and other carcinogens.
4.Genetic- Family history of lung cancer.