In each question, the first and the last sentences of the passage are numbered S1 and S6 respectively. The rest of the passage is split into four parts. These four sentences are jumbled. Read the sentences and identify their correct and logical order.

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S1: Why then, do sharks attack?
P: "The only way a shark can warn you is with its mouth and teeth," says Baldridge.
Q: In murky water it may simply be a case of mistaken identity.
R: Snork bumps and open - mouthed slashings are ways of trying to frighten you off.
S: But the most persuasive explanation is that they perceive their victim as a threat.
S6: Attacks of this kind may be generated by a swimmer who unwittingly interrupts a courting procedure, trespasses in a shark's territory and cuts off its escape route.
The Proper sequence should be: