In hot springs the rising superheated water is cooled below the boiling point by groundwater before reaching the surface. In geysers the superheated water collects in underground pockets.
C. The Roots and Mycelium
Both are the best similar structures between plants and fungi as these parts serves as the channels which transports all the nutrients from the soil/host to the plant/fungi.
Increased exposure to X-rays
I think it’s c but I’m not entirely sure