Which is the correct label for the angle?

"the angle formed by line segments bc and ba measuring 65 degrees."

a.) ∠a
b.) ∠bca
c.) ∠b
d.) ∠cba

The answer to this item is letter D. Angle CBA. Since it is formed by joining line segments BC and BA, its vertex is at B and that B should appear in the middle when the letters are arranged. It does not matter which comes first, whether A or C, so long as letter B is at the middle. 

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