To assist an individual who is having a generalized seizure, you should:

Placing the individual on their side during a generalized seizure is crucial for their safety, as it helps to prevent potential choking. When a person has a seizure, they might lose control of their bodily functions, including the ability to swallow, which increases the risk of aspiration if they vomit. By positioning them on their side, any fluids or secretions can drain out of the mouth, significantly reducing this risk. This position also helps to keep the airway clear.

Additionally, the other choices would not provide the appropriate assistance in this situation. Restraining the individual's movements can lead to injury, as it may cause them to struggle or lead to fractures or bruising. Placing something in their mouth could cause further injury to the person's teeth or jaw and does nothing to protect the tongue. Leaving the room deprives the individual of necessary supervision and support during a potentially dangerous moment. Therefore, laying the individual on their side is the most effective method to ensure their safety during a generalized seizure.