In shade conditions, plants typically show:
Stem elongation (C) is correct here. This is core PHYTOCHROME: once you know the definition or pathway step, Stem elongation is the clear fit. The wrong ones are A) Reduced stem elongation; B) Increased leaf expansion; D) Reduced auxin. If the topic is about gradients or potentials, water/solutes move from higher to lower of the relevant quantity.
Ref: Best CSIR NET Plant Physiology books: Master Unit 6 with Taiz & Zeiger and Salisbury & Ross. Crack Part C experimental questions with top textbooks.