The answer is C. solid iron and nickel
The digestive and respiratory tracts include the pharynx. The pharynx is found at the back part of the throat and is connected to the mouth and the nasal cavity. It then extends to connect into the esophagus and larynx. The pharynx serves as passageway for air during respiration and food for digestion.
Molecules in the solid phase have the least amount of energy, while gas particles have the greatest amount of energy.There are space between particles of matter. The average amount of empty space between molecule gets progressively larger as a sample of matter moves from the solid to the liquid and gas phases.