I have a macro that asks the user to highlight the first row of data
in the worksheet so it can find and separate the worksheet into
several smaller sheets based on the identifier in the first column. I
want to be sure that the user has only selected a single row in the
input box before the rest of the macro executes. I could write code to
get the row number for the top row of the selected range and the row
number for the last row in the selected range and compare them, but
this seems more complicated than it needs to be. Is there an easier
way? Some kind of simple IF statement that tells the user to try again
if there's more than one row in their selection?

Thanks!