Read the following poem by Edgar Allen Poe and answer the question that follows.

A Dream Within a Dream
Take this kiss upon the brow!
And, in parting from you now,
Thus much let me avow‚
You are not wrong, who deem
That my days have been a dream:
Yet if hope has flown away
In a night, or in a day,
In a vision or in none,
Is it therefore the less gone?
All that we see or seem
Is but a dream within a dream.
I stand amid the roar
Of a surf-tormented shore,
And I hold within my hand
Grains of the golden sand‚
How few! yet how they creep
Through my fingers to the deep
While I weep‚while I weep!
O God! can I not grasp
Them with a tighter clasp?
O God! can I not save
One from the pitiless wave?
Is all that we see or seem
But a dream within a dream?
Which of the following best describes what the poem is about?

loss of hope and lack of control
the phenomenon of beach erosion
loss and depression
nightmares and dreams