What role do themes play in historians' efforts to organize information about the past?

A. They help historians focus on the effects of one important idea on
different societies over time.

B. They help historians decide whether or not a primary source is
credible.

C. They allow historians to better understand how earlier historians
interpreted past events.

D. They make it possible for historians to gain a deep understanding
of a particular region.

please delete this answer, i did not mean to answer this.

when a country suffers, for example, a drought period, the market product is affected for a low offer, in this case, potatoes; the government has to tax to the households, which have to give more money for the potatoes which they consume, that situation make them consume substitute goods even through loans, it could increase the financial market movement and the inflationary phenomena, the business has to increase salaries in order to the employees could buy a more expensive food (potatoes) and in order to inflation tha business had to buy expensive supplies in the factor market, while the rest of the world have to gain more money to consume the same amount of potatoes.