Mention one way that tapeworms can be identified in pets.

Tapeworms can be identified in pets primarily by the presence of rice-like segments in their feces. These segments, known as proglottids, are actually fragments of the tapeworm that are shed in the feces and can be seen as small, white, rice-shaped materials. This visual evidence is a direct indication of a tapeworm infection in the animal.

The other options do not specifically indicate a tapeworm infection. For instance, fur color changes can result from various health issues, but they are not directly linked to tapeworms. Similarly, excessive drinking of water may suggest a different medical condition, such as diabetes, and does not relate to parasitic infections. Black patches on the skin can indicate a range of skin problems or infections, completely unrelated to tapeworms. Therefore, the observation of rice-like segments in feces stands out as the definitive sign of tapeworm presence in pets.