Read the following passage and circle the letter A, B, C, or D to indicate the correct answer to each of the questions.

A biography is a narrative of a person's life written by another person. There are usually five main steps in writing a good biography.

1. Choose a subject. Choosing the person you want to write about is, of course, the first step. This could be a celebrity, or someone who is lesser known. You could also write about someone who is still alive or someone who is dead. Most importantly, choose a person who has had an impact on other people, or whose life is interesting.

2. Get permission. Although you can still write about a person's life without his or her permission, it is always better to get the subject's agreement. This will not only help you in your research, but you will also avoid upsetting the person later on if he or she thinks your account is not true.

3. Do your research. You can obtain information through primary sources, e.g. the subject's letters or other personal writings, and interviews with her or him. You can also use secondary sources prepared by someone who didn't know the subject or published at a later time.

4. Choose a format. A biography is usually told in chronological or time order. However, you may also choose to organise the events by themes or specific achievements.

5. Outline, write, and edit. It's a good idea to start with a detailed outline including your main points and the number of chapters. After that, write your first draft. Then revise and edit it until you've got a final version you are happy with.

Writing a biography is not easy, but it is worth the effort. A biography often influences or motivates people, and teaches valuable life lessons.

Alexander Fleming was working in his lab when he was discovering penicillin by accident. A. was working B. when C. was discovering D. by