ANS:A - are of spongy nature

The phrase "are of spongy nature" refers to the characteristic of certain materials, including soils, to resemble or behave like a sponge. Here's what it implies:

1. Porosity: Sponges are highly porous materials, meaning they contain a lot of small holes or void spaces. Similarly, materials described as having a spongy nature often have a high porosity, meaning they contain a significant volume of empty spaces or voids within their structure.
2. Ability to Hold Moisture: Sponges have the ability to absorb and hold water within their porous structure. Similarly, materials with a spongy nature, including certain types of soil containing organic matter or highly compacted soil with significant pore spaces, have the capacity to absorb and retain moisture.
3. Compressibility and Resilience: Sponges are compressible materials that can be squeezed and then return to their original shape when pressure is released. Similarly, materials with a spongy nature, such as some types of soil, may exhibit compressibility and resilience when subjected to external forces like compaction or deformation.
4. Air and Water Exchange: Sponges allow for the exchange of air and water within their porous structure. Likewise, materials with a spongy nature in soils facilitate the movement of air and water through their pore spaces, which is essential for processes like drainage, aeration, and root growth in soil ecosystems.