SAT English Practice Question

The following excerpt is from a science textbook describing an experiment that involves using a magnifying glass to focus sunlight on a piece of paper. The excerpt is written in the third person. What is the best way to rewrite this excerpt to be written in the first person?

1. A.The magnifying glass is used to focus the sunlight onto a piece of paper.
2. B.Using the magnifying glass, the sunlight is focused onto a piece of paper.
3. C.The magnifying glass is used to focus the sunlight onto a piece of paper, which is then held by the experimenter.
4. D.I used the magnifying glass to focus the sunlight onto a piece of paper.