In formal correspondence, the phrase 'With ______ to your message' is commonly used.

• A. Reference
• B. Regarding
• C. Concerning
• D. On

Answer: (A)

The phrase used to connect your reply to a prior message is “With reference to your message.” reference here means the prior message you are referring to, and this forms a formal, polite opening in business correspondence. It clearly signals that you are addressing or replying to what was previously said, which helps keep the communication precise and professional.

This specific noun fits smoothly after “With” and before “to your message,” forming a natural, standard expression. Other options would not produce a correct or natural structure with the exact template “With _____ to your message,” so they don’t convey the intended formal linkage in this sentence. For example, you would instead use “With regard to your message” if you used regard (not provided as an option) in that exact position.