Astar's motion towards or away from us is detected by the of the spectral lines.

A star's motion towards or away from us is detected by the wavelength of the spectral lines.
Because when a star is moving toward us or away from us, the apparent color does not change but there is a change in the wavelength of spectral lines, when the stars are moving towards us, the spectral lines are towards red end and when they are moving away from us the spectral lines are towards the blue end.

A. Animals break down food molecules to obtain energy

B. The remains of the producers are broken down by decomposers.

C. The remains of consumers are broken down by soil decomposers.

Explanation:

Carbon is an important ingredient of the bodily composition of the living organisms. The carbon dioxide released from the organism during the process of cellular respiration. In this the energy from the food molecules are broken down to produce energy in the form of ATP and oxygen. This process results in the libertion of carbon dioxide.

Also the decomposition of the plant and animal dead material by the soil bacteria deposit carbon dioxide in the soil.