Answer:
Tetragonal unit cell.
Step-by-step explanation:
A unit cell is the smallest part of a material which is formed by a well arranged lattice points. Some common types are; face centered, body center, tetragonal, cubic etc
Tetragonal unit cell has a square top and base, with rectangular sides. The internal angles are each, and consists of molecules, atoms, or ions (lattice points) arranged at each corners of the unit cell.
The crystal as described in the given question is a tetragonal unit cell.