Pinus wallichiana belongs to the family Pinaceae. This family is known as the pine family, which includes several species of coniferous trees. Pinaceae is characterized by its needle-like leaves, woody cones, and resinous sap. Pinus wallichiana, also known as the Himalayan pine, is a species of pine tree native to the Himalayas. It is a tall and evergreen tree with long, slender needles and large cones. Therefore, the correct answer is Pinaceae, referring to the family to which Pinus wallichiana belongs.