Excel gives you many quick shortcuts for adding data in the worksheet. You typed a date in cell A$1,$ hovered over the square in the bottom right of the cursor and then dragged down. What feature have you used and what will the highlighted icon allow you to$?$

$1$ point

The feature is called Flash Fill and the highlighted icon will allow you to customize the entries.

The feature is called Autofill and the highlighted icon will allow you reverse the process.

The feature is called Autofill and the highlighted icon will allow you to customize the entries.