Robins migrate south during the winter months to avoid harsh conditions and then return north during the summer. What environmental condition are the robins most likely responding to in order to determine when the seasons are changing?

A.)The tilt of Earth on its axis.
B.)Fluctuations in predator populations.
C.)Changing length of daylight hours.
D.)Increasing availability of water.

The quiver tree grows in southern africa. which of the following plant adaptations is likely to prevent these trees from dying out due to rising desert temperatures? releasing a black powder onto their trunk to absorb more heat from sunlight shifting their growing range towards the equator ability to store water in leafy structures to prevent excess evaporation limiting seed dispersal to nearby locations