What do the international efforts at reducing resource and ecological depletion have in common?
a. they rely on voluntary participation.
b. they came about through the work of the united nations.
c. they began in the 1980’s.
d. they have nothing in common.

Good Morning! International efforts in controlling and reducing the waste of ecological resources have in common the participation of voluntary groups in their implementation. Popular participation, which is not funded, is fundamental to fostering new practices of ecological awareness, bringing great benefits to the environment. Letter: a. They rely on voluntary participation. Hugs!

The one that most represents the earths mantle would be the skin since the mantle is the upper part of the earths depths which is just like the skin of an apple.