To Ensure That Their Populations Are Equal, U

To ensure that their populations are equal, U.S.House and state legislative districts must be redrawn every:

A) five years, after the U.S.Census Bureau updates population estimates.
B) 10 years, after another federal census of the American population is completed.
C) so often, depending on funding, but within 15 years.
D) four years, in order to also correct for possible gerrymandering.