  Suppose that $A,B$ are nuclear, separable ${\rm C}^*$-algebras of stable rank
one and real rank zero, $A$ is unital simple, $B$ is stable and $({\rm
K}_0(B),{\rm K}_0^+(B))$ is weakly unperforated in the sense of Elliott
\cite{Ell}. We show that any unital extension with trivial index maps of $A$ by
$B$ is absorbing.
