I think that the "blank" is best filled by "equal".
This would mean that all people have the same power of decision in a democracy, and if it seems that some people have more than others: in fact they only represent the whole population.
In comparison, in a monarchy, the monarch has more power than the common people.
the answer is agriculture
D. collecting biological specimens. Darwin went to the Galapagos islands to study evolution
By building rafts, leaving 5,000 mean behind followed midnight.
Your answer would be D.
I logic this out in this way:
Exchanging currencies wouldn't be of much use unless you plan to buy something from a country that uses that currency.
Hope this helps.
