For problem $"A"($above$),$ if one of the conditions in the model for this problem was that either project $5$ or project $8$ or both must be selected. This condition is represented by the following constraint:

None of these answers is correct.

$x_5{x}_8$

$x_5+x_{8}1$

$x_5{x}_8$

$x_5+x_8=2$