The correct answer is: A. A change in a cell's genetic material.
Mutations occur in DNA as a result of mistakes during the DNA replication (when repair mechanisms don’t fix it) or as the result of environmental factors (e.g. UV light). Mutations can have positive impact, by increasing the genetic variation or can have negative effect, causing the diseases or cancer.
Explanation:
Make a standard, "dart" design paper airplane
Fold your paper into the basic dart paper plane. Fold carefully and make your folds as sharp as possible, such as by running a thumbnail or a ruler along each fold to crease it. Do not bend up the edge of the wings
Throw the plane at least four more times. Each time before you throw the plane, make sure it is still in good condition (that the folds and points are still sharp). When you toss it, place your toe on the line and try to launch the plane with a similar amount of force, including gripping it at the same spot.
Once you have a good idea of how far your plane typically flies, change the plane’s shape to increase how much drag it experiences. To do this, cut slits that are about one inch long right where either wing meets the middle ridge. Fold up the cut section on both wings so that each now has a one-inch-wide section at the end of the wing that is folded up, at about a 90-degree angle from the rest of the wing.
Make paper planes that are different sizes and compare how well they fly.
Try making paper planes out of different types of paper, such as printer paper, construction paper and newspaper. Use the same design for each.
Some people like to add paper clips to their paper planes to make them fly better. Try adding a paper clip (or multiple paper clips) to different parts of your paper plane (such as the front, back, middle or wings) and then flying it
I hope i helped
