Final answer:
The action associated with patch testing that can be delegated to unlicensed assistive personnel (UAP) is examining the patch area for evidence of a reaction. Therefore, the correct option is 2.
Step-by-step explanation:
The action associated with patch testing that the nurse can delegate to unlicensed assistive personnel (UAP) is examining the patch area for evidence of a reaction. Patch testing is a procedure used to determine allergies to substances by applying patches containing potential allergens to the patient's skin. The UAP can monitor the patch area for any signs of a reaction, such as redness, swelling, or itching, and report their findings to the nurse.