Plasmolysis occurs when plant cell is placed in:
C fits best: Hypertonic solution. Keep the BASICS of PLANT basics straight and Hypertonic solution stands out as the precise answer. Avoid: A) Hypotonic solution; B) Isotonic solution; D) Pure water. Light and flowering items often hinge on which photoreceptor or day-length rule is in play.
Ref: Best CSIR NET Plant Physiology books: Master Unit 6 with Taiz & Zeiger and Salisbury & Ross. Crack Part C experimental questions with top textbooks.