Step 1: Read List II from the other side.
Instead of matching each crystal system A, B, C, D one by one, look at each condition in List II and ask which crystal system it belongs to. This checks the same mapping from the reverse direction.
Step 2: Statement I says all edges and all angles are unequal.
A crystal system with no equal edges and no equal angles, and none of the angles fixed at $90^{\circ}$, is triclinic. So statement I belongs to D (Triclinic).
Step 3: Statement II says two edges equal, third different, all angles $90^{\circ}$.
$a = b \neq c$ with $\alpha = \beta = \gamma = 90^{\circ}$ is the defining condition of the tetragonal system. So statement II belongs to C (Tetragonal).
Step 4: Statement III says all edges unequal, two angles $90^{\circ}$ and one angle not $90^{\circ}$.
This one tilted angle with the rest at $90^{\circ}$, and no edges equal, is the monoclinic condition. So statement III belongs to B (Monoclinic).
Step 5: Statement IV says all edges equal and all angles $90^{\circ}$.
That is the most symmetric case, which is the cubic system. So statement IV belongs to A (Cubic).
Step 6: Put the matches together.
$A \to IV$, $B \to III$, $C \to II$, $D \to I$.
This is the same pairing as reading it forward, which confirms the answer.
\[ \boxed{A-IV,\ B-III,\ C-II,\ D-I} \]
