The correct answer is Real GDP reflects output more accurately than nominal GDP by using constant prices.
Gross domestic product (GDP) represents the sum (in monetary values) of all final goods and services produced in a given region (whether countries, states or cities) over a given period (month, quarter, year). GDP is one of the most widely used indicators in macroeconomics to quantify the economic activity of a region.
In the GDP count, only final goods and services are considered, excluding all intermediate consumer goods from the account. This is done to avoid the double counting problem, when values generated in the production chain are counted twice in the sum of GDP.
It would be A. Factor Loadings
by the oldest symbols called cave paintings formed by rock art
I believe the answer is: Ruling out rival hypotheses
Rival hypothesis refers to two possible alternatives to explain a certain occurrence which would contradict one another. Ruling out rival hypotheses is really crucial in order to improve internal validity of the result, and usually carried out by using control techniques (most important is random assignment).