Read the passage and answer the following questions:
Cancer is one of the most dreaded diseases of human beings and is a major cause of death all over the globe. More than a million Indians suffer from cancer and a large number of them die from it annually. The mechanisms that underlie development of cancer or oncogenic transformation of cells, its treatment and control have been some of the most intense areas of research in biology and medicine. In our body, cell growth and differentiation is highly controlled and regulated. In cancer cells, there is breakdown of these regulatory mechanisms. Normal cells show a property called contact inhibition by virtue of which contact with other cells inhibits their uncontrolled growth. Cancer cells appears to have lost this property. As a result of this, cancerous cells just continue to divide giving rise to masses of cells called tumors.

Which carcinogen present in tobacco smoke is responsible for lung cancer ?

Chemical carcinogen.

The correct answer is Option (2)- Chemical carcinogen.

The carcinogen present in tobacco smoke that is primarily responsible for causing lung cancer is a Chemical Carcinogen.

Chemical carcinogens are substances within tobacco smoke, have the potential to induce genetic mutations and damage DNA, leading to the development of cancerous cells. These carcinogens are a major cause of lung cancer among smokers and are linked to various other cancers as well.