Which of the Following Is True Regarding Porter's Diamond Theory

Which of the following is true regarding Porter's diamond theory?

A) It predicts that countries should be importing products from those industries where all four components of the diamond are favorable.
B) Porter's theory has been proven to be an accurate predictor of the importing and exporting patterns of countries.
C) It predicts that countries should be exporting products from those industries where all four components of the diamond are those areas where the components are not favorable.
D) Porter's theory has not been subjected to detailed empirical testing, so we do not know if it is correct.