Which one of the following should contain maximum DO? ans. molten glacier and ice caps Lake Ground water River

The question seems to be asking which of the following should contain the maximum Dissolved Oxygen (DO). The options are:

1. Molten glacier and ice caps
2. Lake
3. Ground water
4. River

Dissolved Oxygen (DO) is the amount of oxygen that is present in water. It is an important measure of water quality as it indicates a water body's ability to support aquatic life.

Here is a step-by-step analysis of each option:

1. Molten glacier and ice caps: These are typically cold environments. Cold water can hold more dissolved oxygen than warm water. However, these environments are also often isolated from the atmosphere and may not have a constant source of oxygen.

2. Lake: The amount of DO in a lake can vary. It depends on the temperature, salinity, and pressure of the water. Lakes often have less DO than rivers because they are stagnant and do not have a constant flow of water to mix and aerate the water.

3. Ground water: Ground water typically has less DO than surface water because it is isolated from the atmosphere. The DO in ground water often comes from the soil and rocks it comes into contact with.

4. River: Rivers often have a high DO content because they are constantly moving, which helps to mix and aerate the water. They are also in constant contact with the atmosphere, which allows for gas exchange to occur.

Based on this analysis, rivers should contain the maximum Dissolved Oxygen (DO) among the given options.