Final answer:
Product placement is a source of extra revenue for video-game designers and adds an element of reality to their games.
Step-by-step explanation:
Product placement is a technique used by video-game designers where real-world products or brands are integrated into the game. This can include displaying logos or featuring products within the game environment. It is true that product placement can be a source of extra revenue for video-game designers as they can receive payment from companies for featuring their products. Additionally, product placement can add an element of reality to the games by making them feel more immersive and relatable to the real world.