Which of the following statements is correct?

Which of the following statements is correct?
 
  a. Women are increasingly holding high political office and soon will hold up to 40 percent of political positions worldwide.
  b. Only in Western nations have women ever held any type of high political office.
  c. Although women in Western societies have made tremendous gains in holding political office, they never hold office in tribes and chiefdoms.
  d. Across the spectrum and as a norm, women rarely hold important political positions.
  e. Cross-culturally, women are always placed within advisory roles in the political structure.