Verified Answer :

Neuron

Individuals needs to adjust their physical activity to account for possible injuries as they age. People in general become much more injury prone as they age and this is a thing that individuals indeed need to adjust for with age.

Leader

Individuals need to adjust their physical activity to account for reduced flexibility, decreased energy levels, and a loss of balance as they age.

\(\sf\ Answer:\ D)\ ALL\ THE\ ABOVE\)