Obsname level :                              Frank 1                              Joan 2                              Sui 2                              Jose 3                              Burt 4                              Kelly .                              Juan 1   The following SAS program is submitted:  data work . expertise;  set work. levels;  if level = . then expertise = 'Unknown';  else if level = 1 then expertise = 'Low';  else if level = 2 or 3 then expertise =' Medium';  else expertise = 'High';  run;  Which of the following values does the variable EXPERTISE contain? A. Low, Medium, and High only B. Low, Medium, and Unknown only C. Low, Medium, High, and Unknown only D. Low, Medium, High, Unknown, and ' ' (missing character value)     Can anyone help me with its answer with a reasoning ... View more