What is the climax of chapter iv of the story of my life?

a - suddenly i felt a misty consciousness as of something forgotten a thrill of returning thought; and somehow the mystery of language was revealed to me

b - the little blind children at the perkins institution had sent (the doll) and laura bridgmen had dressed it

c - i lay in my crib at the close of the eventful day and lived over the joys it had brought me, and for the first time longed for a new day to come

d - i became impatient at her repeated attempts and, seizing the new doll, i dashed it upon the floor

(A) Suddenly I felt a misty consciousness as of something forgotten a thrill of returning thought; and somehow the mystery of language was revealed to me

Explanation:

The Story of My Life is a heartbreaking story about the challenges faced by Keller and his teacher Sullivan to communicate with each other until Sullivan tried the method of spelling words in Keller's hands. With this method, Keller got a breakthrough into the world of communication.  

For the first time, Keller recognized the word 'water' through the method, and as she explained it in his book, "the word life, awakened my soul, gave it light, hope, joy, released it."

the correct answer can either be a or b because it could be both but you should probally choose b

the krebs cycle and electron transport occur in the mitochondria, though other than that i would need to know more information.