The Backbone of North Atnerica refers to theA．Appalachian Mountains.B．Rocky Mountains.C．Ca

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

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

______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