In spreadsheet software and many programming contexts, a formula always starts with an equals sign (=).
The equals sign tells the system that what follows is not just text or a number, but a calculation to perform.
Signs like plus (+), asterisk (*), and percent (%) are operators used inside the formula, but they do not define it.
Without the equals sign at the beginning, the calculation will not execute as a formula.
Therefore, the correct answer is option (B).