Read the excerpt below and answer the question. the bravest — grope a little — and sometimes hit a tree directly in the forehead – in the poem “we grow accustomed to the dark,” the lines can best be understood to describe
how we struggle for knowledge
how we are inherently clumsy
how we are easily frustrated
how we are prone to misunderstanding

The lines can best be understood to describe how we struggle for knowledge

Explanation:

Darkness in this poem could be a metaphor for uncertainty, so if people get hits and bruises on their way to know who's there in the dark, that means that people, in reality, has to pass through a lot of harsh situations in order to get the knowledge not only of what it's beyond their sight but also to learn how to deal with uncertainty.