What is the default action of the split command on an input file?

What is the default action of the split command on an input file?

A.
It will break the file into new files of 1,024 byte pieces each.

B.
It will break the file into new files of 1,000 line pieces each.

C.
It will break the file into new files of 1,024 kilobyte pieces each.

D.
It will break the file into new files that are no more than 5% of the size of the original file.