Answer: D. Iron rusts
Explanation: Rust is made from different chemicals in the air that come in contact with said metal. That could be acidic rain for example. Water freezing is only changing temperature. Sugar dissolving is breaking down molecules. Salt and pepper mixed in a dish is a physical change (also that's just plain evil to some people but that isn't the point). Your answer will be D. Iron rusts.
Hope this helps!
Overview of oxidative phosphorylation. The electron transport chain forms a proton gradient across the inner mitochondrial membrane, which drives the synthesis of ATP via chemiosmosis
The answer is medicine, agriculture, geology, and archaeology. I know this 100% cause I just took the quiz.
Make an observation.
Ask a question.
Form a hypothesis, or testable explanation.
Make a prediction based on the hypothesis.
Test the prediction.
Iterate: use the results to make new hypotheses or predictions.
The birds adapted to the changes. Since the large nuts were no longer as abundant because of the large birds, the small birds were left with the smaller nuts. Their larger beaks lost their use since the small nuts did not require such well-structured beaks, so the birds started to develop smaller beaks.