Which two storylines can be correctly categorized as science fiction?
a 5-year-old child tells his parents about his past life that he can remember clearly.
a narrator recounts the day his hometown suffered an alien invasion.
a mountaineer describes his ascent to the highest peak in the world.
a teacher takes her class to the past in a time machine to investigate their roots.

The correct storylines would be "A narrator recounts the day his hometown suffered an alien invasion." and "A narrator recounts the day his hometown suffered an alien invasion."

This is because these storylines include pseudo scientific elements and are therefore science fiction. The first story has nothing scientific, it is just mystical and possibly magical, while the third has nothing mystical or magical in it or scientific.