According to the information in the Excel Basics chapter in the nextbook, which of the following statements is true?

$($a$)$

The analyst uses $"$@$"$ to begin all formulas or functions in Excel.

$($b$)$

The MAX function is the largest number of sheets possible in an Excel file.

$($c$)$

An Excel file should never be saved until the completion of the analysis.

$($d$)$

Columns in Excel are labeled alphabetically $($A$,$ B$,$ C$...)$ while rows are labeled numerically $(1,2,3...).$