(N/A) $1$. Assertion $(A)$: By observing the size of an erect image, we can identify the mirror. For a plane mirror, the size of the image is equal to the object $(m=1)$. For a convex mirror, the erect image is always diminished $(m<1)$. For a concave mirror, the erect image is always magnified $(m>1)$. Thus, the assertion is true.
$2$. Reason $(R)$: For a concave mirror, a real image is formed when the object is placed beyond the focus $(u > f)$. The real image and the object coincide only at the center of curvature $(u = v = 2f)$. At this point, the distance between the object and the image is zero. Therefore, the statement that the minimum distance is non-zero is false.
$3$. Conclusion: Since $A$ is true and $R$ is false, the correct option is $(c)$.