The geographical feature that separates the United Kingdom from the rest of Europe is the North Sea.
The North Sea is the water body that lies between the United Kingdom and the continental part of Europe. With France and Benelux being just on the south of it, and the Scandinavian Peninsula on the east. We can also include the English Channel, as it is separating part of the north of France and the south of the United Kingdom.
This was not always the case, and the territory of the United Kingdom was relatively recently (geologically speaking) connected by land with the rest of Europe through a land that is now bellow water called Doggerland, and that was until the end of the last ice age.
It would be the development in agricultural knowledge/technology
Development in agriculture enable hunter/gatherer society to shift their behavior. Before this, they had to keep moving from one place to another in order to seek food to live.
After the development in agricultural knowledge/technology, the society now can stay in one exact place for a long period of time and relied on agricultural product as their main source food.
After living in one same place for a long time, the needs to build things to accommodate their living start to arise. They start to built several things and repeat the process every year. In the end, large cities were developed from the initially small hunter/gatherer society.
The answer to your question is,
e. allow American companies and banks to invest in foreign countries
-Mabel <3