Answer: Option A.
Different beaks were available
Explanation:
Variation is the difference between traits, cells, or characteristics between organisms of any species which is caused by change in genetic information or effect of environmental factors on the expression of genes.
From the question, different beaks were available because there is variation or differences in shapes, sizes and expression.
Answer:
The answer should be C. The cambium produces a waxy substance called suberin which repels water so..
Some chemicals can alter the shape of some enzymes, heat also works (think cooking).