Read the sentence.

i can’t but roll my eyes whenever my sister tells a fib about eating her vegetables so that she can get dessert.

why does the author most likely use the word fib in this sentence?
to emphasize how silly the sister can be
to show that the sister’s lie is harmless
to show that the sister’s lie is serious
to highlight how deceitful the sister can be

To show that the sister’s lie is harmless.

Hi!

The answer to your question would be option B. To show that the sister’s lie is harmless

Explanation:

To find the answer we should first know what a "fib" is. Fib is defined as a lie, typically an unimportant one.

Now that we know that the sister is telling an unimportant lie, we can check with the options and see that option B, to show that the sister’s lie is harmless, is the one that perfectly matches.