Final answer:
The average age of diagnosis for Non-Hodgkin's lymphoma is older, usually in the 60s or 70s, while Hodgkin's lymphoma typically affects younger individuals, predominantly those between 20 and 30, or those over 55.
Step-by-step explanation:
The average age of diagnosis for Non-Hodgkin's lymphoma is generally older, with most patients being diagnosed in their 60s or 70s. Conversely, Hodgkin's lymphoma typically has an average age of diagnosis which is younger, often occurring in individuals between the ages of 20 and 30, with a second peak in those over 55.
The correct answer to the question would be: Non-Hodgkin's average age is older, while Hodgkin's average age is younger, so option a) Older, younger is the correct choice.