A plant cell in isotonic solution becomes:
C fits best: Flaccid. Keep the BASICS of PLANT basics straight and Flaccid stands out as the precise answer. Avoid: A) Turgid; B) Plasmolysed; D) Burst. 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.