The correct answer is a neutral stimulus.
A neutral stimulus (such as a bell, or an object), that is repeatedly followed by unconditioned stimulus, eventually elicits a conditioned response. For instance, in Ivan Pavlov's famous classical conditioning study, he repeatedly paired a neutral stimulus (a ringing bell) that came before an unconditioned stimulus (food), and eventually the sound of the bell alone elicited a conditioned response (salivating) in dogs.
A benefactor or a donor is a wealthy supporter of artists, writers, and scholars
Answer: B. Authorized Congress to implement a graduate income tax
Explanation: The Sixteenth Amendment (Amendment XVI) to the United States Constitution allows Congress to impose an income tax from any source without alotting it among the states on the basis of population.
<u><em>The price of one nation's currency in terms of another nation's currency is called the exchange rate</em></u>
