Which one of the following statements about the Lock Formula option in the Expressions dialog box is false?

The choice indicating that expressions with locked formulas cannot be unlocked is false. In Siemens NX, while locking an expression serves to prevent unintended modifications to crucial calculations or parameters, it is indeed possible to unlock those expressions when needed. Users can manage the locked state as part of their workflow, allowing for flexibility when adjustments are required in the design process.

The other statements accurately describe the functionality of the lock feature in the Expressions dialog box. Locking an expression enhances protection by preventing accidental changes, making it particularly beneficial for maintaining the integrity of critical equations. Moreover, locked expressions are visually distinct; they appear grayed out in the Expressions dialog box and display a lock icon, providing clear feedback to users about their locked status. This visual cue and the grayed-out effect help users quickly identify which expressions are secured against alterations.