Which statement best describes enzymes?
(1) every enzyme controls many different
reactions.
(2) the rate of activity of an enzyme might
change as ph changes.
(3) temperature changes do not affect enzymes.
(4) enzymes are produced from the building
blocks of carbohydrates.

The best which describes an enzyme is 2.
 Every enzyme can control one or more types of reaction whereby the rate of activity of an enzyme will be influenced by PH and temperature.
Enzyme increases its reaction rate by lowering its activation energy. Some enzymes are being used commercially for example in the synthesis of antibiotics.

Ithink that b is correct but just in case wait to see if someone else answers