Question

Identify the wired transmission media for the following: “They are less expensive and commonly used in telephone lines and LANs. These cables are of two types: Unshielded and shielded.”

• A. Optical Fibre
• B. Coaxial Cable
• C. Twisted pair cable
• D. Microwaves

Hint:

Twisted pair cables are cheap and widely used. UTP is most common in LAN connections, while STP provides better noise resistance.

Answer 1

The Correct Option is C

Step 1: Analyze the description.
- "Less expensive and commonly used in telephone lines and LANs" → refers to twisted pair cables.
- They are available as Unshielded Twisted Pair (UTP) and Shielded Twisted Pair (STP).
Step 2: Evaluate options.
- Optical Fibre: Expensive, high-speed, long distance, not telephone/LAN basic usage.
- Coaxial Cable: Used for cable TV and broadband, not primarily for LAN telephony.
- Twisted pair cable: Correct → used in LANs and telephone lines, UTP/STP types.
- Microwaves: Wireless medium, not wired.

Final Answer: \[ \boxed{\text{Twisted pair cable}} \]