Final answer:
The assessment finding that indicates a potential adverse complication associated with taking propanolol is the development and complaint of insomnia.
Step-by-step explanation:
The assessment finding that indicates a potential adverse complication associated with taking propanolol is A: Development and complaint of insomnia. Propanolol is a beta blocker medication used to treat hypertension by slowing down the heart rate. However, insomnia is a known side effect of propanolol, as it can interfere with sleep patterns.