The main reason of the dispersed settlement are Mountainous or heavy forested area, Poor soil fertility, Adverse climatic region, Less availability of arable land.
The correct matches are Vajrai Waterfall- Urmodi river (Maharashtra), Barehipani Falls- Budhabalanga River (Odisha), Dhuandhar Falls- Narmada (Madhya Pradesh), Kunchikal Falls- Varahi river (Karnataka).
The Thermal concept of the origin of monsoon was given by noted astronomer Halley. But there were some faults. Halley overlooked the Coriolis effect and the concept of the passing of latent heat through water vapour.