fill the matrix correctly and the guess the Letter and number of 5th matrix:
PS: I'm sure you won't need options!
| |X| | | | |X| | |X| | | |X| | | | | | |X| | | | | |X| | | O + 17
The first piece moves to the right, the second moves down, the third moves left, the fourth moves up, and so the fifth probably moves right.
The letters and numbers are the sum of X and Y coordinates respectively, with the upper left corner being coordinate $(1,1)$ or $(A,1)$.
Each image introduce its new element at the position given by the coordinate sum of the previous image.
Both movement and new positions wrap around, so when a piece would move over the border it appears next to the opposite border, similarly a piece that appear at for instance $(H,11)=(8,11)$, will wrap around to $(8\mod5,11\mod5)=(3,1)=(C,1)$.