Which of the following is the economic definiton for recesssion?

An economic recession is a significant decline in economic activity, real GPD, real income, employment, industrial production, and sales following a decline in the aggregate demand for at least two quarters.

Explanation:  

In economics, a recession is a business cycle contraction when there is a general decline in economic activity. Recessions generally occur when there is a widespread drop in spending (an adverse demand shock). This may be triggered by various events, such as a financial crisis, an external trade shock, an adverse supply shock, a pandemic or the bursting of an economic bubble. In the United States, it is defined as "a significant decline in economic activity spread across the market, lasting more than a few months, normally visible in real GDP, real income, employment, industrial production, and wholesale-retail sales". In the United Kingdom, it is defined as a negative economic growth for two consecutive quarters.

option d is correct. corroborated sources of historical evidence   is necessary to validate a claim about an event in history.

historians tend to use written sources, but audio and visual materials as well as artifacts are important objects that supply information to modern historians.

historical sources are usually divided into two categories: primary and secondary sources. depending on the historian's intent, some sources shift their designation. determining what type of sources toimplement, and the level of credibility and reliability of those sources, is a significant step in critical thinking for the historian.

explanation:

b. native americans them