Practice question

The right choice is B: Castasterone and brassinolide. In Brassinosteriod, that matches how the process or concept actually works — the other choices mix up related ideas or use the wrong mechanism. Skip these: A) Brassinolide and campesterol; C) Teasterone and cathasterone; D) Dolichol and phytol. A quick check: if an option needs energy, pumps, or the opposite direction of movement, ask whether that really applies.