Catalyst increasing both forward and reverse reaction rate

[TT0]

The question is:

Which takes place when a catalyst is added to a reaction at equilibrium?

A. The point of equilibrium is shifted to the right.
B. The point of equilibrium is shifted to the left.
C. The forward and reverse reactions rates are increased unequally.
D. The forward and reverse reactions rates are increased equally.
E. The value of ΔH has the same magnitude but a different sign.

I chose C because I think that a catalyst would increase the reaction rate of one way. The other way would also increase a bit because of the increased concentration of it. However, the answer is D, they both increase equally. I don't understand how this is possible, could someone explain this?

Thanks

 

[Bystander]

It gets where it's going faster.

 

[Ygggdrasil]

See https://www.physicsforums.com/threads/catalyst-effect-on-equilibria.623300/