Question

Which lines in this excerpt from the poem "A Grain of Sand" by Frances Ellen Watkins Harper indicates its subject?

Answer 1

The lines in this excerpt from the poem A Grain of Sand by Frances Ellen Watkins Harper that indicate its subject for me are:

(Do you see this grain of sand)

(Oh how little seems the span)

In this poem, the narrator is comparing a grain of sand with the significance of human life. She uses the grain of sand to show how small can a part of the beach be, how it is "lying loosely" in her hand and how us, individuals, are like a grain of sand in the Universe, "how little seems the span".  

The idea of the whole poem is to show how small and insignificant can a part of everything seem to be.

Answer 2

The correct answer should be
(Do you see this grain of sand)

The subject is the little grain of sand because it's the focus of the poem and is also the doer of the action of bringing a thought.