Standard Deviation what information is needed to know its relevance

I am unsure which answer is correct but I pretty certain that it is not e even though this seems the most logical choice. You read a research paper that applies to your industry and it says that when people are given a list of facts about your product they are more likely to your product and that the difference between the regular amount of sales and the sales when people read the list of facts is 3 standard deviations. how would you describe the difference of 3 standard deviations (select the best answer)? Select one: a. Cannot tell because the units are not specified. b. It is a small difference because 3 is a small number. c. It is an important difference because a 3 standard deviation difference would be expected due to random chance in less than 1% of the cases. d. It is NOT an important difference because with each sample there is variation and the difference could be due to chance. e. Cannot tell because the sample size is not given Information Many thanks