Which of the following statements is true about catalysts? and why?

a. catalysts slow down the rate of chemical reactions
b. all catalysts are enzymes
c. catalysts are used up during a chemical reaction
d. catalysts lower the activation energy of a chemical reaction

I believe the correct answer from the choices listed above is option D. Catalysts lower the activation energy of a chemical reaction. It is a substance which speeds up a reaction, but is chemically unchanged at the end of the reaction. It provides another pathway for the reaction to occur.

That result from subduction of oceanic plates beneath lighter continental plates. most of the earth's volcanoes are located around the pacific ring of fire because that the location of most of the earth's subduction zones.