THE SOLITARY REAPER

BEHOLD her, single in the field,
Yon solitary Highland Lass!
Reaping and singing by herself:
Stop here, or gently pass!

Alone she cuts and binds the grain,
And sings a melancholy strain:
O' listen! for the Vale profound
Is overflowing with the sound.
No Nightingale did ever chaunt
More welcome notes to weary bands
Of travellers in some shady haunt.
Among Arabian sands:
A voice so thrilling ne'er was heard
In spring-time from the Cuckoo-bird,
Breaking the silence of the seas
Among the farthest Hebrides.

Read the given sentence and answer the following question from the options given below. 'Stop here, OR gently pass!'

The part of speech for 'OR' is :

Conjunction