Answer:
The mother dolphin followed Kara because Kara knew where her baby calf is.
Step-by-step explanation
When Kara had rescued the white dolphin calf which belongs to the mother. The dolphin was found caught in a fishing net and rescued by Kara with help from Felix, her father and the marine rescue team.
The calf was then led to a tidal pool where it was to recuperate. The mother dolphin followed Kara because Kara was taking it to where the calf was.
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