A) There are two bell shaped curve and normal distribution has a single bell shaped curve hence False

B)Though avg salary for two groups could be distributed normally they are not centered around the same mean or else the two bell shaped curve would occur at the same place hence False

C) The graph does show two bell shaped curve so it could be the case that there are two groups of different number of people each normally distributed

D)The graph shows that there might be two types of data that is normally distributed but if it is a case of a single set of data then the graph is not normally distributed and more importantly we do not know what is the mean so we cannot make assumptions about where the data is skewed hence False

E)Though the option mentions that two set of data are normally distributed, the smaller data set rather will have a higher mean than the large set of data hence False

From POE C is the best option.

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This is my response to the question and may be incorrect. Feel free to rectify any mistakes