The correct answer is B) of or relating to the study of the brain and nervous system.
In the article "What is Love?", the best definition for the word “neurological”? is "of or relating to the study of the brain and nervous system."
Neurological refers to the study of the nervous system in the human body. A neurologist is a doctor who studies and treats nervous systems disorders. When referring to Love and the effect this emotion has on humans, the nervous system participates in the transmission of "sensations" and information to the brain, that it reflects back to our senses to create the feeling of being in love.