Water potential is sum of following components:
Go with C — Ψs + Ψp + Ψg + Ψm. Under WATER POTENTIAL, this is the standard explanation you’d use in class: it names the real driver or definition, while the rest are nearby but wrong. Not these: A) Ψs + Ψp; B) Ψg + Ψm; D) Ψd only. When two options sound similar, choose the one that matches the textbook definition most tightly.
Ref: Best CSIR NET Plant Physiology books: Master Unit 6 with Taiz & Zeiger and Salisbury & Ross. Crack Part C experimental questions with top textbooks.