Yes, you can definitely use symbols in a drop down list in Excel. Here's how you can do it:

1. First, select the cell where you want to create the drop down list.
2. Go to the Data tab in the ribbon and click on Data Validation.
3. In the Data Validation dialog box, select List from the Allow drop down menu.
4. In the Source field, type in the character code for the symbol you want to use. For example, if you want to use the tick mark symbol, type in "=CHAR(252)" (without the quotes).
5. Click OK to close the dialog box.
6. Now, when you click on the cell, you should see a drop down list with the tick mark symbol as one of the options.
7. If you want to add more symbols to the list, simply separate them with a comma in the Source field. For example, if you also want to include the X mark symbol, you can type in "=CHAR(251),CHAR(252)" (without the quotes).
8. You can also change the font of the cell to Wingdings (or any other font that contains the symbols you want to use) to make sure the symbols display correctly.

That's it! You should now be able to use symbols in your drop down list. Let me know if you have any questions or if there's anything else I can help you with.