Which of the Following Occurs Among Adults Who Are Experiencing

Which of the following occurs among adults who are experiencing age-based systematic decreases in cardiac output and maximum oxygen uptake?

A) Immune system functioning is less efficient.
B) There is a general loss of strength and speed.
C) Tissues in all parts of the body become more elastic and flexible.
D) There is a loss of bone mineral and an increase in the wear and tear of the joints.