Which of the Following Is a "Third Variable" Explanation for the Correlation

Which of the following is a "third variable" explanation for the correlation between life changes and physical health problems?

A) Problems with physical health cause an increase in anxiety, which in turn causes stress.
B) Life changes cause an increase in anxiety, which in turn increases the chances of problems with physical health.
C) Problems with physical health necessitate changes in lifestyle, which in turn increase stress.
D) People with certain personality traits are more likely to experience life changes and also more likely to have health problems.
E) Problems with physical health are not always associated with anxiety.