The correct answer is the mountain frogs in a lab setting with no UV rays exposure.
The frog populations, which do not acquire the ultraviolet radiation would function as a good control group. In this case, as the influence of the radiation is the variable under examination, thus, a group that acquires no radiation would exhibit no variation, and thus, would function as a control group that could be compared against the frogs, which do receive the radiation.
The right answer is -boiling or autoclaving.
In a chemical reaction when the temperature increases, protein denaturation occurs with rates that can be increased. The presence of water promotes denaturation. In a system having a hydrophilic phase and a hydrophobic phase, the denatured proteins under the action of the temperature will be placed at the hydrophilic / hydrophobic interface.