The receptor for brassinosteroids is:
Correct option is C, BRI1. In Brassinosteriod problems like this, the accurate statement is BRI1; the others are common mix-ups. Not these: A) TIR1; B) GID1; D) PYL. Tissue transport questions usually turn on xylem vs phloem, living vs dead cells, or source vs sink.
Ref: Best CSIR NET Plant Physiology books: Master Unit 6 with Taiz & Zeiger and Salisbury & Ross. Crack Part C experimental questions with top textbooks.