9. Which of the following statements is true?

&a. Developing countries rely more heavily on direct taxes than do developed countries.

&b.Developing countries rely more heavily on indirect taxes than do developed countries.

&c. Developing countries rely more heavily on personal income taxes than do developed countries.

&d.Developing countries rely more heavily on social security taxes than do developed countries.

&e. Developed countries rely more heavily on import and export taxes than do developing countries.