Step 1: Think about the audience
Radio listeners are often driving, working or cooking. They hear each word once and cannot go back. Anything that makes the talk heavy will lose them. We test each rule against this fact.
Step 2: Rules that help the listener
Talking in a chatty, friendly tone (B) makes the listener feel spoken to personally. Using vivid, imagined words (D) lets the listener build a picture, which radio cannot show. Both help.
Step 3: Rules that hurt the listener
Technical jargon (A) confuses people who do not know the field. Complex sentences (C) need re-reading, which is impossible on air. Both hurt.
Step 4: Match with the options
We need an option that has B and D and nothing else. Option 4 is exactly that.
Step 5: Why options 1, 2 and 3 fail
Option 1 adds jargon (A). Option 2 adds both jargon (A) and complex sentences (C). Option 3 adds A and C but drops B. So only option 4 is right.
Step 6: Recheck with a real example
Think of a popular FM show. The host chats in plain, friendly talk and uses lively phrases that make you picture the scene. The host does not read out technical terms or long twisting lines. This real picture agrees with B and D, and it again rules out A and C. So option 4 stands.
Final Answer:
The RJ needs a conversational style and imaginative words: B and D only.
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