[Solved] The most common vectors used in DNA therapy experiments are _____. A) modified human cells B) retroviruses and adenoviruses C) antisense oligonucleotides (AONs) D) bacteria E) naked DNA Negative Message: Communication that conveys a refusal, denial, or unwelcome news to the receiver. Sincere Apology: An expression of regret that is genuine and heartfelt, indicating true remorse for actions or words that caused harm. Bad News: Information that is unwelcome, disappointing, or negative, often requiring careful communication. Message Shortness: The characteristic of conveying information in a brief and concise manner.