In an Excel document, which action should be taken if you want your information which falls across a selection of cells, to form part of one cell? Select all that apply:

Align text center button.  


Merge across button.  


Merge & center button.


Merge cells button. 

Merge across button.

Merge & center button.

Merge cells button.

The correct answer is:

- Merge across button.
- Merge & center button.
- Merge cells button.

To form part of one cell, the actions that should be taken in an Excel document are:

1. Merge cells button: Select the cells that you want to merge, then click on the Merge cells button. This will combine the selected cells into a single cell, with the content spanning across them.

2. Merge & center button: After merging the cells, you can also click on the Merge & center button to both merge the cells and center the content within the merged cell. This is useful for aligning and formatting the information.

Please note that the Align text center button is not directly related to merging cells. This button is used to align the text within a cell, but it does not merge cells together.

So, the correct options to select are:
- Merge & center button
- Merge cells button