Answer:
Forward
Step-by-step explanation:
For every force acting on an object at rest, there is an opposite and equal force acting on that same object. In this case, for Lucy to fall backwards, that means that there is a force acting backwards on Lucy, but for Lucy to still be able to stand upright and not yield to the force of falling backwards, then that means more force is exerted to keep her in the stable position that she is, hence the direction of the total force on Lucy is forward.