Answer:
The correct answer is William Somerset Maugham.
Step-by-step explanation:
William Somerset Maugham is a renowned author of novels, stories and plays.
His specialization was short stories.
Regarding the quote, it was published in a book called "Maybe You Should Write a Book" designed for all those who want to start as writers.
There is no book or rule to start writing novels or stories, and that is what Maugham meant by saying "There are three rules for writing a novel. Unfortunately, no one knows what they are." That is why this quote is included in the book.
You can always study other authors as inspiration and look for many sources and examples to start writing, but the reality is that there is no basic rule to do this.