The choices can be found elsewhere and as follows:
The rate will increase, by a factor of more than 50.
The rate will decrease, by a factor of more than 50.
The rate will increase, by a factor of less than 50.
The rate will decrease, by a factor of less than 50.
I believe the correct answer is the third option. The effect of it on the rate of reaction would be that the rate will increase, by a factor of less than 50. Hope this answers the question.