I looked all over the Internet, and saw that there is another option that you didn't include, and which is actually the correct answer. Bays best facilitate the building of ports, not these options.
The soil named chernozem is a black colored soil found in Russia and has a high percentage of the humus contents that is 4 to 16% and consists of the folic acid and phosphorous and the ammonia.
Thus is very fertile soil and has a high agricultural yield and this soil consist of the high moisture storage capacity thus is supportive of the large agricultural cultivation.
