Why do the father and aunt refer to Firoozeh as a rock ?

Read the excerpt from it's our world, too! : young people who are making a difference.the author’s purpose in this excerpt is to

The story line remains the same. the kids live in what was then one of the remaining beachfront slums, down the coast from the expensive malibu area. the beach was ruled by surfers, but in the afternoon, when the waves died down, some of the surfers, or their younger brothers, fooled around on skateboards. one day, skip engblom, the shop owner, comes up with a key breakthrough, polyurethane wheels: "they grip." with the additional traction, the z-boys try skating the sides of the big, open drainage canal that runs through the area. then comes a brainstorm: because of a drought, the area's swimming pools were drained. the kids started "borrowing" pools when the owners weren't home, to skate the curved sides.” where did “the lords of dogtown” originally practice their tricks? a. the beach c. an open drainage canal b. empty pools d. none of these

Emily is reading her friend's story. it uses transition words like and emily can tell that this story's organization is a) sequence of events b) cause and effect c) compare and contrast d) question and answer