To answer this question, we need to analyze each program option and identify if any of them contain a syntax error.
Option A) Proc Sort data=sasuser.mysales; by city; run;
This program is a valid SAS code. It uses the PROC SORT statement to sort the dataset sasuser.mysales by the variable city. It does not contain any syntax errors.
Option B) Dat sasuser.mysales; set mydata.sales99; run;
This program contains a syntax error. The correct keyword to define a dataset is DATA, not DAT. Therefore, the correct statement should be DATA sasuser.mysales;. This option contains a syntax error.
Option C) Proc Print data=sasuser.mysales label; label city='Mumbai'; run;
This program is a valid SAS code. It uses the PROC PRINT statement to print the dataset sasuser.mysales with a label. It also assigns the label 'Mumbai' to the variable city. It does not contain any syntax errors.
Option D) None of the above
This option is incorrect because option B contains a syntax error.
Therefore, the correct answer is B) Option B. This option contains a syntax error because it uses the incorrect keyword DAT instead of DATA to define a dataset.