There are two areas of the brain that are important parts of the reward circuit. What is the chemical that is released into the brain as a "reward"?
O Adrenaline
O Serotonin
Norepinephrine
Dopamine

B.) Serotonin I think. I may be wrong

Explanation:

i'm not sure i completely understand your question, but i will do my best.

i think the answer you are looking for is sequence. (see below)

a repeated melodic fragment would be best defined as repetition, while repeated chords (different or the same) could be a chord progression. however, you then mentioned the chord and melodic fragment beginning on higher or lower pitches, in that case, the answer could be best defined as a sequence. the definition of a sequence is as follows: "the restatement of a motif or longer melodic (or harmonic) passage at a higher or lower pitch in the same voice."

let me know if this !

the answer is letter b. false. fugue is a complex musical composition that does not occur or come together at the same time. in fact, it is composed of a number of voices or parts where the theme is introduced in one part and successively imitated in other parts.