Which items are examples of artificial riding aids?

Artificial riding aids refer to tools or devices that are used to assist a rider in communicating with their horse during riding. Spurs and crops are specifically designed for this purpose, helping the rider to convey cues to the horse more effectively. Spurs can be applied to the horse's sides to encourage forward movement or response to leg pressure, while a crop can reinforce commands through gentle taps or strikes.

In contrast, the other options encompass natural aids or methods that depend on the rider's body movements or voice. For instance, the rider's voice, weight, legs, and hands all involve natural body motions or verbal cues that are instinctive rather than mechanical. Thus, spurs and crops stand out as specific, designed implements that fall within the category of artificial riding aids, making them the correct answer.