This seems to be a geometry question in Bulgarian. Here's the translation of the problem:

Problem 3: Given that $AM = 6 \, \text{cm}$, $AB = 12 \, \text{cm}$, $MN = 4 \, \text{cm}$, and $MM | AB$ (which means that the segment $MN$ is parallel to $AB$), what is the length of segment $AC$? The possible options for the length of $AC$ are: a) 3 cm
b) 8 cm
c) 9 cm
d) 12 cm

The diagram shows a triangle $ABC$ with points $M$ and $N$.

To solve this, we'll likely need to use properties of similar triangles and the parallelism condition, as parallel segments in triangles imply proportionality.

Would you like me to walk through the steps for solving this problem?