While obtaining a client’s health history related to smoking cigarettes, the nurse plans to determine the client’s smoking pack years. What information should the nurse obtain for this calculation? Select all that apply.

Choice A rationale Packs of cigarettes smoked per day is essential information for calculating smoking pack years. Choice B rationale The number of attempts to quit smoking is not required for calculating smoking pack years. Choice C rationale The client’s current age is not required for calculating smoking pack years. Choice D rationale While this helps you calculate the total years if the client hasn't done the math themselves, the age itself is not a variable in the final formula. Choice E rationale The number of years the client smoked is essential for calculating smoking pack years.