Rick A. answered 03/27/19
Experienced SAS Professional
From SAS documentation:
DSD (delimiter-sensitive data)
specifies that when data values are enclosed in quotation marks, delimiters within the value are treated as character data. The DSD option changes how SAS treats delimiters when you use LIST input and sets the default delimiter to a comma. When you specify DSD, SAS treats two consecutive delimiters as a missing value and removes quotation marks from character values.
The main idea behind using the DSD option (there is no = sign after the option) is that it makes it very easy to read in .CSV files because CSV files are comma-delimited (not space-delimited) and they enclose any field values containing a comma with quotation marks.