Viet said he would be doing experiment 10 oclock following day

A. Viet said that he would be doing a experiment at 10 o’clock following day.

B. Viet said he would be doing an experiment at 10 o’clock following day.

C. Viet said he would be doing a experiment at 10 o’clock the following day.

D. Viet said that he would be doing an experiment at 10 o’clock the following day.