Final answer:
Crystals in the same crystal system have unit cells with the same symmetry, but they might not exhibit identical properties, because properties are affected by other factors like bonding and composition.
Step-by-step explanation:
The question is concerned with the characteristics that crystals in the same crystal system share due to the geometry of their unit cells. Unit cells are the smallest repeating unit that reflects the structural symmetry of the entire crystal lattice. A crystal system's unit cells will have the same basic symmetry, which does not necessarily mean that the crystals themselves will exhibit identical properties.
The correct answer to the question is that crystals in the same crystal system all have unit cells with the same basic symmetry, even if the crystals themselves don't exhibit identical properties (Option D). This is because while the unit cell establishes the symmetry, there are other factors such as bonding, composition, and force interactions that determine the crystals' physical properties.
Different types of ionic compounds can crystallize in the same crystal structure if they have similar ionic sizes and stoichiometries. This shows that while the macroscopic properties of crystals might vary, their microscopic structures can be closely related through their unit cell patterns and crystal lattices.