Anytime the pronoun le is followed by the pronoun lo, los, la, las,you need to change the le to se. Another example of when to make this pronoun switch would be in the following sentence:
Le cuento un relato a Francisco.
Se lo cuento.
It is important to remember that se changing to le always affects the indirect object, not the direct object. In this example, le is referring to Susana and la to the apple.
