Answer: D. Actuaries
Explanation: According to the investment advisers act of 1940, an investment adviser is any individual who is involved in the business of providing guidance to others with regards to investments and securities for a compensation. It is important that a person must meet the whole definition in order to be regarded as an investment adviser.
There are however, various exclusions to this definition. These people may coincidentally comply with the definition of an investment adviser, but are by law not an investment adviser. These include teachers, engineers, lawyers and accountants. Giving advice on investments are incidental to their profession and so this does not qualify them as investment adviser.