A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
Hi,
I would do this with 'Data Validation.
Somewhere out of the way enter Yes and No in 2 cells then select the cell where you want this dropdown and:-
Data tab|Data Validation|DataValidation|Select 'List' in the 'Allow' Box.
Click the small icoun to the right of the 'source' box and navigate the where you entered Yes/No and select thos 2 cells by dragging with the mouse. OK out and your done.
Tip. To make them visible i always apply a background colour to data validation cells.