Frog eggs are usually attached to vegetation or rocks near the surface of a pond. Tadpoles can use essentially all areas of a shallow pond, or the top few feet of a deeper pond or lake. Adult frogs can live on land or in the water. A frog's life would be least likely to be disrupted by a change in the

For a change in the environment that surrounds them.

Explanation:

Frogs and toads are amphibians that have the ability to live in both environments, that is why their respiratory system is highly adapted to extreme situations such as sudden climate changes, among others.

This modification of the environment many species would not tolerate because generally species always develop, live and reproduce in a single environment, such as humans, which is only in the terrestrial environment.

It is very difficult for frogs not to be able to adapt or survive climate change since they have the ability to adapt their respiratory system to two totally different media such as water and air.

A frog's life would be least likely to be disrupted by a change in the bottom or benthic zone

Explanation:

In aquatic environments, it occurs a predictable variation in temperature, light, salinity, nutrients, oxygen, and other factors that might limit the distribution of living beings. The water body might be divided into vertical and horizontal strata according to these factors.      

The euphotic zone corresponds to the area where occurs photosynthesis, while the aphotic zone corresponds to the depths where light does not reach, and photosynthesis does not occur.

The shallow area near the shore is called littoral, characterized by the presence of many plant species. Frog eggs are usually attached to vegetation or rocks in these shallow areas, where vegetation is abundant and there is plenty of light.

Beyond the littoral, there are open areas known as limnetic photic areas, limited in depth by the light penetrance. In relation to light penetrance, photosynthesis might be performed up to 50-100 meters, the máximum depth of active photosynthetic radiation penetrance. The deep zone is under the limnetic zone and is the point where respiration equilibrates with photosynthesis. Tadpoles can use both areas, especially the limnetic area.

Adults make use of the three areas: the littoral shallow areas, the limentic zone and the deep zone, which they might use while searching for food or scaping from predators.    

The third deepest stratum is the benthic zone, near the bottom and characterized by being poorly lighted and a decomposition place.  Also, the available oxygen is very low. There is a high anaerobic bacterial activity of decomposition.  Frogs (or any other vertebrate) would not be able to live in these areas, mainly because of the oxygen lack.

A change in this stratum, or in the bottom, would hardly cause any disruption to the frogs lifes.

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