All of the following will increase the rate of reaction EXCEPT: A
Increasing the temperature

B
Adding a catalyst

C
Increasing the concentration of a reactant

D
Decreasing the pressure

the old alchemists made significant contributions to science even though there starting premises were off a bit. their conclusions after failure would steer them into better directions for investigation. science is no more than close observation and the initial mistakes result in rethinking and retrying experiments.

a is the correct answer