In this poem, Columbia refers to America. How does the reference to mother earth support the theme of these lines?
Celestial choir! enthron'd in realms of light,
Columbia's scenes of glorious toils I write.
While freedom's cause her anxious breast alarms,
She flashes dreadful in refulgent arms.
See mother earth her offspring's fate bemoan,
And nations gaze at scenes before unknown!
(from "To his Excellency General Washington" by Phillis Wheatley)

a.It likens American citizens to children and their patriotism to parental love.
b.It represents America as a maternal figure and other nations as her children.
c.It suggests that life comes from earth, and America is its newest shining child.
d.It depicts nations as children engaged in sibling rivalry in the form of wars.

This poem was directed to George Washington in 1775, before American Independence was declared and American's victory against the tyrannical british rule was still uncertain, but Wheatley wrote this poem to praise and keep inspiring the American Revolution “named Columbia,” which was an embodiment of freedom. Under this context, Wheatley metaphorically represents America as a maternal figure and other nations (her offspring) as her children:

See mother earth her offspring's fate bemoan,

And nations gaze at scenes before unknown!