Correct option is C
Trendelenburg or knee–chest position shifts fetus upward, relieving cord compression and preserving blood flow until delivery.
Explanation of options: (a) ✘ Supine worsens cord compression due to gravity. (b) ✘ Lithotomy is for instrumental delivery, not cord prolapse. (c) ✔ Correct; Trendelenburg/knee–chest relieves cord pressure and is first-line. (d) ✘ Sitting upright increases compression further.