All of the Following Are Reasons Why an Association Relationship $\underline{\text{ except: }}$

All of the following are reasons why an association relationship may not imply a causal relationship $\underline{\text{ except: }}$

A) the association may be due to pure chance
B) the association may be the result of the influence of a third common factor
C) both variables may be the cause and the effect at the same time
D) the association may be hypothetical
E) both c and d