The correct answer is Cell. In a computer worksheet application like Microsoft Excel, a cell is the fundamental unit where you input and store data, which can include text, numbers, formulas, or functions. Each cell is uniquely identified by its column letter and row number (e.g., A1, B5), forming the grid structure of the worksheet. It is the intersection point of a row and a column.
Option A, Row, is incorrect. A row is a horizontal series of cells in a worksheet, identified by a number (e.g., Row 1, Row 2). While cells are part of a row, a row itself is not the basic unit for data entry.
Option B, Column, is incorrect. A column is a vertical series of cells in a worksheet, identified by a letter (e.g., Column A, Column B). Similar to a row, a column contains multiple cells but is not the singular unit for entering text and numbers.
Option D, Range, is incorrect. A range refers to a group or block of selected cells in a worksheet. While it involves cells, it is a collection of basic units rather than the basic unit itself.