The backbone of Canadas economy is______.A．forestryB．agricultureC．service industryD．manufa

The Pennies is known as the backbone of England.（)

The Backbone of North America refers to theA．Appalachian Mountains.B．Rocky Mountains.C．Cas

The economic backbone of Canada includesA．fishing.B．tourism.C．agriculture.D．entertainment

______is（are)considered as "the backbone of the continent" in America, and is（are) also kn

______is sometimes called the "backbone of England".A．The Sperrin MountainsB．The Cambrian

As the backbone of the North American continent, ______is known as the Continental Divide