TOPIC: Control account query

Which of the following statements is true regarding Control Account?
SELECT THE CORRECT ANSWER

Used as a Tool and Technique in Activity Definition process
Used to estimate cost at a level lower than the work package
Used to control costs of the project
Used in Integrated Change Control

The answer says option a.
But control account is not a tool and technique..shouldnt it be option c?
PMBOK Page 161 says control account is a management control point, where scope, budget, schedule are integrated and compared to earned value for performance measurement

From where did you get this question?

It is from simplilearn