What does parallel transmission mean?

• A. Sending all 8 bits at the same time over 8 separate wires, each send 1 bit
• B. Sending bits sequentially over a single wire
• C. Transmitting in only one direction at a time
• D. Transmitting with modulation

Answer: (A)

Parallel transmission means sending multiple bits at the same time across several wires, so an entire data word is transmitted in one moment. Picture eight wires carrying eight bits at once, one bit per wire, so the 8-bit value arrives together rather than bit by bit. This is different from serial transmission, where bits are sent one after another on a single line. The other ideas—sending in only one direction, or using modulation—describe timing/duplex or signal encoding aspects, not the number of wires used to move all bits at once. Parallel transmission is fast over short distances, like inside a computer or on a local data bus, but it becomes costly and prone to timing mismatches (skew) as distances grow, which is why longer connections often use serial methods with proper synchronization.