The commercial revolution allowed for two key components.
First they allowed joint stock companies to put money into a company.
If the company failed not all your money was lost.
Second the commercial revolution allowed for major raw resources to be brought to Europe, which in turn was finished products.
True would be the answer youre looking for.Hope this helps!!
I would think that they had begun to build up resistances to the virus's and conditions they were exposed to.
The UK, France, Canada, The Soviet Union, China, and later, The United States