D is the coupe number for sure.. And regarding 4 berth or 2 berth, I dont have much idea... most probably it would be a 4 berth if u have booked ticket for just one person or for 3 or more person.
please wait...Translate to HindiD, bilkul coupe number hai.. Aur 4 berth ya 2 berth ke baare mein mujhe zyada pata nahi hai... Jyadatar yeh 4 berth hogi agar tumne ek vyakti ya teen ya zyada vyakti ke liye ticket book kiya hai toh.