During a geography class, the teacher discussed alluvial soils with the students, giving them various clues. Which of the following clues provided by teacher is correct?
Clues:
i. This type of soil is typical of the Deccan trap (Basalt) region spread over northwest Deccan plateau and is made up of lava flows.
ii. This is the most widely spread and important soil.
iii. Mostly these soils contain an adequate proportion of potash, phosphoric acid and lime.
iv. These soils develop under tropical and subtropical.