Consider the following code that will assign a letter grade of $\text{'}$A$\text{'},\text{'}$B$\text{'},\text{'}$C$\text{'},\text{'}$D$\text{'},$ or $\text{'}$F$\text{'}$ depending on a student's test score.

$)(60)(70)(80)(90$

This code will work correctly in all cases

This code will work correctly only if grade $60$

This code will work correctly only if grade $<mn\; id="EditorElement\_196221">6</mn><mn\; id="EditorElement\_196222">0</mn>$

This code will work correctly only if grade $<mn\; id="EditorElement\_196162">7</mn><mn\; id="EditorElement\_196163">0</mn>$

This code will not work correctly under any circumstances