What is a cell in Microsoft Excel?

Correct option is C

In Microsoft Excel, a cell is the intersection of a row and a column in a worksheet. It is the basic unit where data is entered, and each cell has a unique address based on its row and column coordinates.
(a) A separate file used to store data: This is incorrect because a cell is not a file; it's a single data point within a worksheet.
(b) A single worksheet within a workbook: This is incorrect because a worksheet consists of multiple cells, not just one.
(d) A small diagram or chart: This is incorrect because diagrams or charts are graphical elements, whereas a cell is a basic data unit within a worksheet.