Answer
d, Gluteus medius and tibialis anterior
Work Step by Step
These muscles function in the swing phase of walking as well as in the preparatory stance:
The gluteus medius positions the heel for the strike; it also abducts the lower limb as well as extends the thigh and rotates the hip externally.
The tibialis anterior is one of the muscles of the anterior compartment of the leg. In the swing phase of walking it dorsiflexes the ankle and lifts the foot from the ground as it maintains the dorsiflexion.