Short Answer 
The process involves three steps: first, select an item by clicking and holding it; second, drag the item to the answer box and release it to place it correctly; and third, modify or clear answers by dragging items to the trashcan or clicking it to reset everything.
Step 1: Select the Item
Begin by clicking on an item in the list or the group of pictures located at the bottom of the problem. Ensure you hold the mouse button down as you select the item. This action is crucial for moving the desired item into your answer box.
Step 2: Drag and Place the Item
While still holding the mouse button, drag the selected item to the correct position in the answer box. It is important to accurately place the item to reflect your understanding of the problem. Once you have positioned it properly, release the mouse button to drop it in place.
Step 3: Modify or Clear Your Answers
If you wish to change your selection or remove an item, drag it over to the trashcan icon. This action allows you to recycle your choices. To completely clear all your answers, simply click the trashcan, which will reset the answer box for a fresh start.