Is this multiple choice?!
Answer:
Cancer disease occurs when the abnormalities occurs during cell division of stem cells. Stem cells are those cells which are produced in the body and used by the body when the cells are older or get damaged. When the division of these stem cells are uncontrollable, cancer occurs which spread to the surrounding cells. When a large group of cancer cells grow in size, it turns into tumor.
A lit candle needs to draw oxygen from the air in order to continue burning. If you limit the amount of air available, the candle's flame eventually goes out once it uses up all the oxygen. Lit candles in smaller jar stop burning first because the oxygen trapped in the jar are fewer than the ones in bigger jars.