In the following passage, some words have been deleted. Fill in the blanks with the help of the alternatives given. Select the most appropriate option for each blank.

Comprehension:
Smoking causes mutation in cells leading to cancer. Quitting smoking can help reverse the (1)______ risk; and it can replenish cells that actually (2)______ those of a person who has never smoked. The (3)______ you smoke the more mutations you have. The (4)______ damage to the cells lining the airway and lungs can (5)______ to cancers in the lungs, oesophagus, larynx and pharynx.