What is the best investment for seniors in Canada?

Can you provide me with some insights on what might be the most suitable investment option for seniors in Canada? Are there any specific financial instruments or assets that cater well to the needs and risk appetites of this demographic? Additionally, how do factors such as market volatility, accessibility, and potential returns come into play when selecting the best investment for seniors in the country? Is there a particular strategy or set of considerations that one should keep in mind when making such an important financial decision?