Two computers that communicate with each other use a simple parity check to detect errors for ASCII transmissions. Which of the following events will always lead to an undeleted error?

• one bit or any odd number of bits inverted in a block of data during transmission
• two bits or any even number of bits inverted in a block during transmission
• one bit or any odd number of bits inverted in a byte during transmission
• two bits or any even number of bits inverted in a byte during transmission
• None of the above