(a)
Both Assertion and Reason are true and Reason is the correct explanation of Assertion.
Explanation
CSV (Comma Separated Values) is indeed a file format for data storage that resembles a text file. CSV files are plain text files that typically use the .csv extension and contain tabular data organized into rows and columns. The information in CSV files is organized with one record (or row) on each line, and each field (or column) within a record is separated by a comma.