If $\angle \text{CBD}$ is a [right angle](https://artofproblemsolving.com/wiki/index.php/Right_angle), then this protractor indicates that the measure of $\angle \text{ABC}$ is approximately

$\text{(A)}\ 20^\circ \qquad \text{(B)}\ 40^\circ \qquad \text{(C)}\ 50^\circ \qquad \text{(D)}\ 70^\circ \qquad \text{(E)}\ 120^\circ$
We have that $20^{\circ}+\angle ABD +\angle CBD=160^{\circ}$, or $\angle ABD +\angle CBD=140^{\circ}$. Since $\angle CBD$ is a right angle, we have $\angle ABD=140^{\circ}-90^{\circ}=50^{\circ}\Rightarrow \boxed{\mathrm{(C)}}$.