Blue light activates phototropin by:
That points to B: Uncaging the kinase domain. Compared with the other options, Uncaging the kinase domain is the one that correctly describes the Phototropin+All concept. The wrong ones are A) Protein cleavage; C) Protein degradation; D) Nuclear import. If you’re stuck, eliminate anything that contradicts a basic fact you already know for this topic.
Ref: Best CSIR NET Plant Physiology books: Master Unit 6 with Taiz & Zeiger and Salisbury & Ross. Crack Part C experimental questions with top textbooks.