AA

Let's break this down step-by-step: 1. We're told David and Billy are alternators, so they must be in the Diamond group. 2. This means Adam and Cam must be in either Golden (truthful) or Silver (liars) groups. 3. Let's analyze each person's statements: **Adam:** - If truthful, his statements contradict the given info about David and Billy. - If a liar, his statements could be consistent. **Billy:** - As an alternator, one statement must be true and one false. - "I am an alternator" is true. - "I am an Engineer" must be false. - "Cam is a liar" could be either true or false. **Cam:** - If truthful, his statements contradict the given info about David. - If a liar, his statements could be consistent. **David:** - As an alternator, one statement must be true and one false. - "Exactly two of us are liars" is false (we know two are alternators). - "I am a Doctor" and "Billy is an Advocate" - one must be true, one false. 4. From this analysis, we can deduce: - Adam is likely in the Silver group (liar) - Cam is likely in the Silver group (liar) - Billy is not an Engineer - David might be a Doctor (if this is his true statement) 5. The only person we haven't ruled out as the Engineer is Adam. Therefore, **Adam is most likely the Engineer**.