One of These is Not Like the Others

Why isn't Lesotho the odd one out in 2, since it's the only land-locked one, Djibouti the odd one out in 3 since it's the only one with a low HDI, New Zealand the odd one out in 4 since it's the only island, the Everglades the odd one out in 6 since it's the only lowland region, Durban the odd one out in 9 since it's the only one one with an urban agglomeration population below 10 million, Potato the odd one out in 10 since it's the only one where the root is eaten, Thames the odd out in 11 since it has a discharge that is orders of magnitude smaller than the others, and Cayenne the odd one out in 12 since it's the only one where English is not the main language spoken?