A. I have a meeting at 10 a.m.; please be on time.
B. I have a meeting at 10 a.m. please be on time.
C. I have a meeting at; 10 a.m. please be on time.
D. I have a meeting; at 10 a.m., please be on time.
Answer: I have a meeting at 10 a.m.; please be on time.