The correct option is E self-deprecating
In the given poem the author likens her writings or books to a child or ‘offspring’, produced by her weak brain. She criticizes herself for all the errors in her writings as "blemishes" and intends to mend them but only ends up making it worse. Thus the tone of the author can be best described as self-deprecating. Therefore option E is the correct answer. Options A,B,C,D are incorrect answers.