sample1.xlsx

Sample file attached. How do I combine the data in columns B-E into column A? Obviously in my sample file you'd use a simple cut/paste but my actual file has hundreds of columns and rows so cut/paste isn't an option. I need to move all the data into column A. Maybe this is simple but I can't figure it out nor find a similar post as I'm not sure the best way to search for this topic. Thanks for your help.