Barry Has Been Depressed for Some Time

Barry has been depressed for some time. How will his depression affect the likelihood that he will have a heart attack?

A) The disorders are very different and do not affect on one another.
B) The depression actually reduces the chances because it tends to control eating and exertion.
C) For reasons that are not yet clear, the depression tends to raise the chances that he will suffer a heart attack.
D) The depression will increase the risk for a heart attack because it will lower his immune system functioning.