2. In a triangle, the area (unit: $\mathrm{cm}^{2}$) is numerically equal to its perimeter (unit: $\mathrm{cm}$), then the radius of its inscribed circle is ( ).
(A) $2 \mathrm{~cm}$
(B) $3 \mathrm{~cm}$
(C) $4 \mathrm{~cm}$
(i) Sern
2. A.

Let the semi-perimeter of the triangle be $p$, and the inradius be $r$, then the area of this triangle is $p \cdot r$. According to the problem, we have $p r=2 p$. Therefore, $r$ $=2$.