In the following passage, some words have been deleted. Read the passage carefully and select the most appropriate option to fill in each blank.
Cancer is a disease in which some of the body’s cells grow (1)__________ and spread to other parts of the body. Cancer can start (2)__________ anywhere in the human body, which is made up of trillions of cells. Normally, human cells grow and multiply- through a process called cell division- to (3)__________ new cells as the body needs them. When cells grow old or become damaged, they die, and new cells take their place. Sometimes, this orderly process(4)__________ down, and abnormal or damaged cells grow and multiply when they shouldn’t. These cells may form tumours, which are lumps of tissue. Tumours can be cancerous or (5)__________.
Select the most appropriate option to fill in blank 1.