Why were nepal and bhutan generally able to remain independent when their neighbors were taken over by outsiders

C. naturally in the environment

Since wxyz is 4, halfof that would be 2.

Magma forms by partial melting of upper mantle and crust. partial melt means that only a fraction of the available material forms a melt, and that the remainder stays solid. the partial melt rises because of its lower density and ascends through he crust. this is so conclusive mean the answer would be magma igneous rocks or balistic magma.

Answer erosion,oil spills,pollution,tourism,urban development;