What is the difference between sentence and clause?

Plz i need someone to write me a narrative from scratch

Which situation might occur in a conflict of character versus nature? a. a society disapproves of a character's behavior. b. a character suffers from a serious illness and eventually dies. c. two characters argue over a difference of opinion. d. a character is unable to decide on his opinion of another character.

Which of these novels is considered an important precursor to science fiction