(c) glass slab
When light passes obliquely through a glass slab, the emergent ray is parallel to the incident ray but shifted sideways — this sideward shift is called lateral displacement.
Source: Light – Reflection and Refraction, Section 9.3.1
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The key phrase is "laterally displaced" — this is the defining property of refraction through a rectangular glass slab. The two parallel faces cause equal and opposite bending, so the ray emerges parallel but shifted. A prism disperses light; a lens converges/diverges it; a plane mirror reflects it. Only a glass slab produces lateral displacement without change in direction.