Which situation most likely developed as a result of gerrymandering?

a. most of a state's political contributions come from donors in a
single, wealthy congressional district

b. a state loses one of its congressional representatives during
reapportionment and must redistrict.

c. congress passes a new law strictly limiting state governments'
ability to change their congressional district borders.

d. a state is sued for intentionally creating a congressional district
with a majority african american population.