Trenches form at sites where
a. one plate descends beneath another.
b. erosion cuts into the continental shelf.
c. two plates diverge under the sea.
d. the tops of undersea volcanoes collapse.

Where do most people living in australia and new zealand descend from? a. most people living in australia descend from germany, while most people living in new zealand descend from france. b. most people living in australia descend from spain, while most people living in new zealand descend from ireland. c. most people living in australia and new zealand descend from britan and ireland. d. most people living in australia and new zealand descend from spain and france.