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A network administrator provides an IP address of 128.135.0.142 and a subnet mask of 255.0.0.0.  Once a ping is attempted, it fails.  Which of the following options is the most probable cause of the failed ping?()

A.0 is not valid in an IP address
B.128 is a reserved network
C.The subnet mask should be 255.255.0.0. since it is a class B
D.A network problem has occurred since IP and subnet are valid

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