During the initial visit with the nurse at the fertility clinic, the patient asks what effect cigarette smoking or heavy alcohol intake has on the ability to conceive.What is the nurse's best response?

"Smoking and a large alcohol intake can affect the quantity of sperm.”.

"Smoking or heavy alcohol use has no effect.”.

"After your first semen analysis, we will see if there will be any difficulty.”.

"Only if you smoke more than one pack a day will you have difficulty.”.