Your marketing lead has asked you to run an A/B test with a new design for an in-app advertisement. You are interested in identifying any statistically significant difference between the mean conversion rates driven by the ads. After establishing control and treatment groups,. Which of the following would be your null hypothesis?
a) The mean of the control group is greater than the mean of the treatment group
b) The mean of the control group is less than the mean of the treatment group
c) There is a difference between the mean of the control group and the mean of the treatment group
d) There is no difference between the mean of the control group and the mean of the treatment group