Assuming that the sentence is part of an informal conversation, which alternative is CORRECT? The sentence is part of a formal text. The sentence ...

Assuming that the sentence is part of an informal conversation, which alternative is CORRECT?

The sentence is part of a formal text.
The sentence is part of an informal text.
The sentence is part of a poem.
The sentence is part of a song.
a) The sentence is part of a formal text.
b) The sentence is part of an informal text.
c) The sentence is part of a poem.
d) The sentence is part of a song.
e) It is not possible to determine the text type based on the given information.