Which of the Following Is the Best Conclusion for an Oral

Which of the following is the best conclusion for an oral presentation?

A) Well, that's about it! If you have questions, see me later for contact information.
B) To ensure that all employees are able to interact effectively with our diverse customers, I encourage you to approve this diversity training program.
C) Thank you from the bottom of my heart for being here today. I really appreciate being able to speak to you today.
D) Before I conclude, let me add two more important points that will impress you with the features about our software.