Final answer:
The Mississippi River forms a delta as it enters the Gulf of Mexico.
Correct answer is A
Step-by-step explanation:
The geographical feature that the Mississippi River forms as it enters the Gulf of Mexico is a delta.
A delta is an often triangular-shaped section of land formed as the waters of a river slow down and split into many channels as they deposit sand and silt that has been carried downriver.
Correct answer is A