Which of the following adaptations helps reptiles survive in desert environments?

Thick scaly skin is a crucial adaptation for reptiles living in desert environments. This type of skin is made up of keratin, which significantly reduces water loss, a vital survival factor in arid conditions where water is scarce. By having thick, scaly skin, reptiles minimize evaporation, enabling them to retain moisture more effectively. This adaptation is particularly advantageous in environments that expose them to high temperatures and low humidity, allowing them to thrive where many other organisms would struggle.

The other options, while they may represent adaptations beneficial in different contexts, do not align with the specific challenges faced by reptiles in deserts. Thick fur is more suited to mammals facing cold environments, swimming ability does not address the direct issue of water conservation, and coloration can be useful for camouflage but does not specifically address the need to withstand extreme dryness or retain moisture.