need explanation picture is added

QUESTION 11 A medical statistical data analyst collected pulse rates of a set of female patients using medical records. For a certain statistical test, he must transform the data by subtracting 5 points from each value of the data set. Which of the following is correct regarding the mean and standard deviation of the transformed data set? O the mean is decreased by 5 and the standard deviation remains the same the mean remains the same and standard deviation decreased by 5 O both mean and standard deviation decreased by 5 the mean remains the same and the standard deviation decreased by 5