In Which of the Following Scenarios Would the Gini Coefficient

In which of the following scenarios would the Gini coefficient measure zero?

A) People earn the same income.
B) John receives a wage of $1 per hour.
C) The king ends up with all the nation's income.
D) There is a one-to-one ratio of income to population.
E) 100 percent of the income is held by 100 percent of the population.