JAMB - Biology (2001 - No. 2)

Amphibians are mostly semi-aquatic and spend part of their time on land and part in water. They typically start out as larvae living in water, but some species have developed behavioural adaptations to bypass this. 

Amphibians require moist habitats, and relative humidities of about 80% work well for most species. Hence, they live in water as well as a moist land. Option B