Answer :
The United States protects Canada from the threat of a nuclear attack are NATO. Thus, option (a) is correct.
What is attack?
The word “attack” refers to a violent act that is done with the intent to harm or to make a physical or verbal attempt to harm or destroy.
The 1949 North Atlantic Treaty Organization (NATO) is referred to by the acronym NATO. The cornerstone of Canadian security and defense policy is its primary commitment to global peace and security.
Therefore, option (a) is correct.
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