Hey there! Hello!
Generally, the author's tone is the expression of the author's attitude/viewpoint towards something in their writing. The author may make certain choices about their diction (word/phrases), syntax (grammar), and amount of formality (the amount of formality/informality in the writing) to convey their stance on something they're writing about.
I believe the "emotional effect of a story" is the author's mood, which is how the writing affects the reader/makes the reader feel, mostly found in the vibe/atmosphere given off in the author's writing. Mood and tone are two different aspects of writing, so I believe your answer is false.
Hope this helped you out! Feel free to ask me any additional questions if you have any. :-)