Which Is a Valid Explanation for the High Recidivism Rate

Which is a valid explanation for the high recidivism rate?

A) The advanced age of most released offenders makes them more likely to commit crimes.
B) The low intelligence of most released offenders makes them more likely to commit crimes.
C) Most released offenders have a biological propensity to commit crimes.
D) The lack of education and training of most released offenders makes them more likely to commit crimes.