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A. y=±x

B. y=±x

C. y=±x

D. y=±x

A.                              B.

C.                              D.

A.y=±                                                       B.y=±

C.y=±                                                       D.y=±

A.y=±x                                   B.y=±x

C.y=±x                                   D.y=±x

A.y=x                       B.y=x

C.y=x                       D.y=x