The correct option is D. Strengthening a response in the brain due to repetition is called long-term potentiation.
Explanation:
In psychology, long-term potentiation is a therapy used to strengthen the synapses between nerves so that a response can be made more efficient over time. For example, when a mice is thrown in a pool it will swim in the pool until it finds a tunnel to hide. If this phenomenon occurs again and again, then the mice will learn the path to the tunnel and will be able to reach it earlier.
