16. in microsoft word, when you highlight existing text you want to replace, you are in

Well the way you replace text is you go to the home tab and you select the text and then you go all the way to the right and there should be a find and replace button and when you click that button the selected text should appear in there and you just type in what you want to replace in the replace box and hit replace all and it will change all the text.

To answer your question I say that you are on the home tab.

Comment me or something if I didn't answer your question.

Just trying to get some points : p sorry bro