what can cause a tumor to form?
parasites cancer respiration digestion pesticide radiation ovaries weathering
A B C D E F G H
Cancer begins when a cell begins dividing uncontrollably.
cancer may cause a tumor to form
what can cause a tumor to form? (A) parasites (B) cancer (C) respiration (D) digestion (E) pesticide (F) radiation (G) ovaries (H) weathering