Gram - the rest are all part of the american system which is not often used in science
I not really sure what the answer is
I believe that you are supposed to notice that the striations in the contracted muscle fibers are much closer together than the striations in the uncontracted muscle. Therefore, it would appear that somehow the striated parts of the muscle are being pulled closer together somehow. Glycerinated muscle retains the organized structural array of myosin thick filaments and actin thin filaments, actin associated proteins like troponin and tropomyosin which regulate contraction, and the functional capacity for contraction.
Some elements mentioned above, such as oxygen are present in organic compunds in many occasions, but from all of the options, the one that is always present is:
A. Carbon
Carbon is found in all organic compunds because of the bonds it can form, being able to form up to 4 covalent bonds.
Hope it helped,
BioTeacher101