In each set of terms given below, there is an odd one and cannot be grouped in the same category to which the other three belong. Identify the odd term in each set and name the category to which the remaining three belong. Example: Ovary, Fallopian tube, Ureter, Uterus. Odd term: Ureter. Category: Parts of female reproductive system.
Sewage, Newspaper, Styrofoam, Hay.
Topic: Biodegradable waste
Answer
Odd term: STYROFOAM. Category of the others: BIODEGRADABLE WASTES.
Sewage, newspaper and hay are all BIODEGRADABLE — organic matter that bacteria and fungi can break down into simple substances returned to the soil.
STYROFOAM is expanded polystyrene, a synthetic polymer. No organism possesses enzymes capable of digesting it, so it persists for hundreds of years.
THE TEST that sorts almost any such list: ask whether the substance was ever ALIVE, or came from something alive. Sewage, paper (from wood pulp) and hay all were; Styrofoam was not.
NEWSPAPER is the near-miss that catches students — it looks manufactured, but paper comes from wood pulp and composts readily.