Ducklings follow their mother due to imprinting.
C or d
because of the passage you can find the answer
Trophic level 3 represents the secondary consumers
Trophic level 4 represents the Tertiary consumer
When the concentration of a certain solute is low inside the cell with respect to the cell's external environment, then the cell performs active transport of the solute from the cytoplasm with a low concentration of solute within the cell to the cell's external with a high concentration of the solute. This process of active transport requires the need of energy in the form of ATP to drive the pumps that are present on its cell membrane.