Read the poem below and answer the question that follows. “La Belle Dame sans Merci: A Ballad” by John Keats

O, what can ail thee, knight-at-arms, Alone and palely loitering? The sedge has withered from the lake, And no birds sing. O what can ail thee, knight-at-arms, So haggard and so woe-begone? The squirrel’s granary is full, And the harvest’s done. I see a lily on thy brow, With anguish moist and fever-dew, And on thy cheeks a fading rose Fast withereth too. I met a lady in the meads Full beautiful—a faery’s child, Her hair was long, her foot was light, And her eyes were wild. I made a garland for her head, And bracelets too, and fragrant zone; She looked at me as she did love, And made sweet moan. I set her on my pacing steed, And nothing else saw all day long, For sidelong would she bend, and sing A faery’s song. She found me roots of relish sweet, And honey wild, and manna-dew, And sure in language strange she said— “I love thee true.” She took me to her elfin grot, And there she wept and sighed full sore, And there I shut her wild wild eyes With kisses four. And there she lullèd me asleep, And there I dreamed—Ah! woe betide!— The latest dream I ever dreamt On the cold hill side. I saw pale kings and princes too, Pale warriors, death-pale were they all; They cried—“La Belle Dame sans Merci Thee hath in thrall!” I saw their starved lips in the gloam, With horrid warning gapèd wide, And I awoke and found me here, On the cold hill’s side. And this is why I sojourn here, Alone and palely loitering, Though the sedge is withered from the lake, And no birds sing.

Source: Keats, John. “La Belle Dame sans Merci: A Ballad.” Poetry Foundation. Poetry Foundation, n. d. Web. 24 June 2011. Determine the meter of this poem.

Which sentence describes the metrical pattern?
The meter is iambic with 8 feet in the first 3 lines; the last line has 4 feet.
The meter is iambic with 4 feet in the first 3 lines; the last line has 2 feet.
The poem is written in blank verse.
The poem is written in free verse.