In total how many "Rows" are there in a spreadsheet?

The correct option is 65,536.

In older versions of spreadsheet software, such as Microsoft Excel (specifically versions Excel 97 through Excel 2003), the maximum number of rows supported in a single worksheet is 65,536.
This limit is based on binary computer storage limits. Specifically, it represents the maximum value that can be represented by 16 bits of data, which is:
2¹⁶ = 65,536 rows.

While modern versions of Excel (Excel 2007 and newer) support up to 1,048,576 rows, the standard limit associated with legacy formats (like .xls) and basic spreadsheet configurations remains 65,536 rows.