Well, the definition of uninformed is to not have knowledge on a particular subject or subjects and to be a fool is someone who acts unwisely or silly. So, an uninformed fool would be someone who is not knowledgeable and acts foolishly.
C. For is the preposition
Answer:
Dear *name*
I am so glad to hear of your success in in your class 10th final board examination. I felt so pleased that I wished I were there to congratulate you personally.
The result has proved that hard work brings good result. You were so much laborious. My parents always gave me your example. My parents already confident that you would come up with good result. They were very much pleased to hear about your progress.
Please be encouraged and continue you hard work so we get happiness news always. Your future is very bright. My father has sent you a lot of love and hearty congratulations on your bright performance.
With lots of love and best wishes again.
Yours lovey *name*
Yes. The authors of biographies are biased towards various parties involved in various things that they are writing about. They might modify sentences, paragraphs and even chapters about the incidents in the life of the person about whom the biography is. This bias and impurity is the reason why autobiographies are better than biographies although none are totally pure.