The correct option is (c).
Explanation
The distribution of water on Earth is highly uneven. The hydrosphere consists of water in oceans, ice caps, groundwater, lakes, and the atmosphere. The primary distinction is made between saline water (oceans and seas) and fresh water.
Statement-wise Analysis:
- Statement 1 is Incorrect: The oceans contain the vast majority of Earth's water. Saline water constitutes approximately 97.3% of the total water on Earth. Therefore, it is significantly more than 90%.
- Statement 2 is Correct: Fresh water accounts for only about 2.7% (often rounded to 2.5%–3% in various scientific texts) of the total water available on Earth. This small fraction supports all terrestrial life dependent on fresh water.
- Statement 3 is Correct: Of the total fresh water available, approximately 70% (specifically around 68.7%) occurs as ice sheets and glaciers in Antarctica, Greenland, and mountainous regions. Only a small fraction (less than 30%) is stored as groundwater, and an even smaller percentage exists as surface water in rivers and lakes.
Key Takeaway:
While Earth is known as the "Blue Planet," roughly 97% of its water is saline and unfit for human consumption. Only roughly 3% is fresh water, the majority of which is locked in ice caps and glaciers.