The researchers noticed that a few of their five hundred subjects had skipped a rather personal in their survey, which created illegitimately missing data. Which of these is a reasonable approach to addressing the missing data if the values cannot be obtained?

A$.$ Revise the survey to delete the personal question.

B$.$ Discard all rows $($observations$)$ with missing values.

C$.$ Use Excels RAND$()$ function to generate the missing values.

D$.$ Personally contact all survey subjects and ask them for a verbal response