The mexican was intended to address mexico's need for a national and revolutionary art.

The answer is

Mexican Muralism

Explanation:

Mexican muralism was a movement and promotion of mural painting starting in the 1920s with social and political messages as part of efforts to unite the country under the post Mexican Revolution government. It was headed by “the big three” painters, Diego Rivera, José Clemente Orozco and David Alfaro Siqueiros.

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."

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