5. Now there are two equally sized equilateral triangles, Alpha and Beta, each with a line segment connecting the midpoints of two sides. As shown in the figure, Alpha and Beta are positioned symmetrically left and right, but the line segments inside Alpha and Beta are asymmetric. Starting from the positions shown in the figure, Alpha moves horizontally to the right until it overlaps with Beta and then moves away. At each position during the movement, the figure formed by Alpha and Beta contains several triangles. In the position where the number of triangles is the greatest, the figure contains ( ) triangles.
A. 9
B. 10
C. 11
D. 12
Analysis: During the translation of Triangle A, there are several triangles in the figure formed by A and B with the following situations, as shown in the figure below. Note that a dynamic approach should be used to analyze the translation process.
Therefore, the answer is $C$.

