I think that the best answer from the options is the following one:
B. lightly regulated markets depressing wages for unskilled workers
The thing is, unskilled workers cannot really pose many demands for their pay, because they can be replaced by other workers. This is what has led to low wages of the unskilled workers, while increasing the wealth of the richest, who own the production means.
I would say plate movement caused it partially however flooding may also have helped
Developed countries have better medical facilities because they have more money and are able to afford equipment which is often very expensive. Due to having more money, their medical facilities can be equipped more expensively. While this doesn't always mean it is a better facility, it often is the case.
So in a nutshell, because developed countries have more money, they are also able to provide better healthcare and better medical care in their medical facilities.
