When does the branch$-$and$-$bound algorithm choose NOT to branch the current node?

When you hit an integer result from the Integer Programming

When the LB$($lower bound$)$ returns a better objective value than the best feasible IP$($integer programming$)$ objective value you have seen before

When the LB$($lower bound$)$ returns an equal or worse objective value than the best feasible IP$($integer programming$)$ objective value you have seen before

When LB$($lower bound$)$ is infeasible