D because the others harm the bird instead of helping
Some examples would be slate, phyllite, and gneiss.
Water cycles through organisms and rivers.
It will be cooler if you close to a body of water
Answer:
they carry out experiments to understand it
Explanation:
Scientists raise hypotheses which are tested by experiments made under controlled conditions in order to explain a particular topic. When a hypothesis is confirmed by the experimental data, the evidence obtained from this experiment provides the basis to increase the scientific knowledge about a particular issue. In consequence, experimentation can be considered as a critical step in the scientific method and research aims to advance knowledge of a particular phenomenon by confirming a hypothesis, which must be testable (i.e. verifiable as a result of further experimentations).