A Retail Outlet Wants to Replace a Broken Ice Cream $\mathrm{X}_{1}+\mathrm{X}_{2}<$

Multiple Choice

A retail outlet wants to replace a broken ice cream vending machine with one of two models. The purchase of model 1 is captured by variable X1. Taking a value of 1 and 0 would represent that machine 1 is not purchased. X2 is similarly defined. One of the constraints for this problem would be

A) $\mathrm{X}_{1}+\mathrm{X}_{2}<$ 1
B) $\mathrm{X}_{1}+\mathrm{X}_{2} \leq$ 1
C) $\mathrm{X}_{1}+\mathrm{X}_{2} \geq$ 1
D) $X_{1}+X_{2}=$ 1
E) $X_{1}+X_{2}>$ 1