To determine the mirror image of the given figure when a mirror is placed at line MN, we must flip the characters horizontally. Each character will appear as it would if viewed in a mirror.

Let's analyze each character in the figure:

1. The letter q will appear reversed, resembling the letter p.
2. The number 7 will resemble a flipped 7, where the horizontal stroke is on the opposite side.
3. The letter r will appear as a mirrored r, curving the opposite way.
4. The letter R will have its curve on the opposite side when mirrored, resembling a backward R.
5. The shape resembling a ∩ will become a ∪ when mirrored.
6. The letter f will look like a reversed f.
7. The letter W will resemble a mirrored W, similar to an upside-down M.

Now, let's compare this with the provided options:

The correct option is the one that reflects all these changes:

This option perfectly matches the expected mirror image we described above. Thus, it is the correct answer.