Answer:
A pedigree
Explanation:
A pedigree is the record of descent of an animal, showing it to be purebred. With a pedigree, a dog breeder would easily have proof of his purebred dogs' heritage.
<h3>Hope this was helpful!</h3>
They are all layers of the earth
1.) Problem: Diff. Shape of the moon
<span>Hypothisis: earth, sun, n moon locations creates a shadow </span>
<span>Experiment: her experiment </span>
<span>Observation: Researching </span>
<span>Conclusion: she is yet to make one </span>
<span>2.) Size of balls - make them accurate </span>
<span>Research: use multiple sources </span>
<span>The amount of light: keep using the same light</span>
The answer is A:
The SUGAR-PHOSPHATE CHAINS form the sides, and the BASE PAIRS form the rungs