Which is the best evidence that rocks found deep underground were once exposed at the surface?

a
the rocks have been melted by a magma.
b
the rocks have been broken by faults.
c
the rocks have been weathered by water.
d
the rocks have been folded by pressure.

The boiling point of propanoic acid is higher than that of 1-butanol because: propanoic acid has a higher molecular weight than 1-butanol. propanoic acid is more soluble in water than 1-butanol. propanoic acid is a better hydrogen bond donor than 1-butanol. propanoic acid forms hydrogen bonded dimers and 1-butanol does not. 1-butanol forms hydrogen bonded dimers and propanoic acid does not.