Answer: I would contend that the right answer is the A) The red tulip opened its petals.
Explanation: Just to elaborate a little on the answer, it can be added that Emily Dickinson was passionate about plants and flowers. She could identify many of them, and she often referred to them in her poems—roses, daisies, and so on. In this poem she is describing a solitary red tulip that lay beneath a tree. When the flower, protected by its cradle, felt the speaker's gentle touch, the flower "put on her carmine suit," that is, it opened its petals, as in recognition of the speaker's kind gesture.