Is there a more specific way you could word this
The answer is B. Retirement
Retirement benefits is the program that employees could use in order to prepare themselves for the period where they longer able to work.
This system usually being done by curring a certain percentage of employee's total salary and allocate it to their retirement account and will be accessible to them in the future
Your heart rate can change due to a number of things including even breathing a certian speed, people who exercise has a slower heart beat then someone who doesnt exercise.
Or even if something is wrong with your heart, your heart rate can change too.