Blender 2.8 how to change toolbar's tools? I'm quite new to Blender and I've been using 2.8 to teach myself 3D modelling and more.

Following a tutorial I must have done some kind of manipulation that changed my default selection tool from box to lasso. As you can see in this screenshot of my toolbar, the lasso selection tool is there instead of the box one, which transformed the latest "left click and drag for box selection" to lasso selection instead, and I don't especially want to go back to pressing 'B' for box selection now.



This is probably a simple shortcut that I triggered unintentionally but I cannot undo it and find nothing regarding Blender 2.8's toolbar customization. How can I change the selection tool from lasso back to box ?
At the bottom right corner of the lasso select tool icon you can see a little white arrow head pointing down. Left click on this and slowly drag your mouse downwards.

This will open a menu where you can choose other selection tools.