Not sure if you don't have the answer yet but the answer is limited water...i just took the quiz.
Agricultural consumption refers to the consumption, or eating, of a place's agriculture, or farmed resources, such as wheat, hay, crops, etc. However, it may also refer to the "using up" of a place's resources. For example, take the phrase, "The economy consumed the country's resources." The economy didn't actually eat the resources, but used them up. Either works depending on the situation, but most likely, the question is looking for the first answer :)
The water cycle transports a plethera of microorganisms, and many of them are harmful for human beings. These include bacteria, protozoa, viruses, and lavae of high-ordered parasytes. Some of the aforementioned are Giardia, Cyptospordium, Shigella, E. coli, hepatitis A virus, and enterovirus.
Waters can also carry chemical wastes such as pesticides, and heavy metals dissolved in them. It is common to hear about acid rain as a result of pollution, and it originates as a result of mixing sulphur dioxide and nitrogen oxide with water molecules in the atmosphere.
There are several technological improvements over the past 100 years that have made the availability of clean water to communities a lot easier, and not only depend on boiling water. Filtration is the most common practice, it traps most unwanted particles and microorganisms, but it should be accompanied with chemical disinfection, which uses halogens to oxidize essential celluar structures and enzymes. In the present, chemical disinfection can even be achieved with adding a pill to a specific volume of water.
A bunch of Scandinavian warriors and merchants, who were actually called Varangians, started expanding into Russia during this time, subduing the local Slavic tribes & forming the Kievan Rus.
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.