Which of the following was a preliminary step in making a stained glass piece
a.

artists cut individual pieces of glass

b.

the painters add details with emulsion

c.

designer drew a composition on a wood panel

The answer is "c.  designer drew a composition on a wood panel".

The term stained glass can allude to colored glass as a material or to works made from it. All through its thousand-year history, the term has been connected only to the windows of holy places and other noteworthy religious structures.  

As a material stained glass will be glass that has been shaded by including metallic salts amid its fabricate. The colored glass is made into recolored glass windows in which little bits of glass are orchestrated to shape examples or pictures, held together (generally) by portions of lead and bolstered by an unbending edge.

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 !

i dont think it is true