The most important day I remember in all my life is the one on which my teacher, Anne Mansfield Sullivan, came to me. I am filled with wonder when I consider the immeasurable contrasts between the two lives which it connects. It was the third of March, 1887, three months before I was seven years old.

On the afternoon of that eventful day, I stood on the porch, , expectant. I guessed vaguely from my mother's signs and from the hurrying to and fro in the house that something unusual was about to happen, so I went to the door and waited on the steps. I did not know what the future held of marvel or surprise for me.

—The Story of My Life,
Helen Keller

What is the central idea of the passage?

The day she met her teacher was the “most important day” of Helen’s life.
On March 3, 1887, Anne was seven years old.
Helen was waiting on the porch and sensed something important was happening.
Helen Keller knew something unusual was about to happen.