What are some effects of permafrost?

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.

None   they are   equally likely to occur on any plate boundary

The area they r in. this  the answer.

Ithink this answer here is a or d