In computer networks, which of the following sets lists only common basic network topologies used to connect devices in a local area network?

Introduction / Context:
Network topology describes the arrangement of devices and communication links in a computer network. Basic topologies are studied in introductory networking courses and form the building blocks for more complex designs. Understanding common topologies helps in designing, troubleshooting, and optimizing networks. This question asks you to identify the set that contains only standard network topologies used in practice.

Given Data / Assumptions:

• We are considering fundamental local area network topologies.
• Common examples include bus, star, ring, and mesh topologies.
• Some options mix valid topologies with shapes that are not standard network topologies.
• The correct set should not contain invented or purely geometric names that are not used in networking.

Concept / Approach:
A bus topology connects all devices to a single shared communication line. A star topology connects each device to a central hub or switch. A ring topology connects each device to exactly two neighbors, forming a loop. A mesh topology provides multiple paths between nodes, with full mesh connecting every node to every other node. These are standard textbook topologies. Options that include shapes like polygon, circle, hexagon, or sphere are not standard named topologies in basic networking and should be rejected.

Step-by-Step Solution:
Step 1 List the commonly taught basic network topologies: bus, star, ring, mesh, tree, and hybrid. Step 2 Compare each option with this list and check whether all elements are valid topologies. Step 3 Notice that option A contains star, bus, ring, and mesh, all of which are standard topologies. Step 4 Observe that the other options introduce shapes such as polygon, circle, square, and hexagon that are not typical topology names, making them incorrect.

Verification / Alternative check:
Any standard computer networks textbook or reference lists star, bus, ring, and mesh as core topologies. Tree and hybrid are also present in many classifications, but geometric terms like polygon, circle, or sphere are not described as formal topologies. Therefore, the set that contains only well known basic topologies is option A, which matches standard terminology.

Why Other Options Are Wrong:
Option B includes polygon, which is a geometric figure, not a standard network topology, so the set is invalid. Option C contains only geometric shapes that are not used as canonical network topology names in networking. Option D mixes mesh, which is valid, with binary tree, hypercube, and hexagon. While binary tree and hypercube may appear in advanced network design discussions, they are not typically listed as basic LAN topologies in introductory courses, and hexagon is not a standard topology name. Option E lists line, grid, cylinder, and sphere, which again are geometric or abstract shapes rather than recognized basic network topologies.

Common Pitfalls:
Students sometimes confuse geometric shapes with network topologies because many diagrams use geometric patterns to visualize connections. Another pitfall is overlooking mesh as a standard topology because it is more complex than bus or star. Recognizing the canonical names as presented in syllabus and standards documents is important for exam preparation and professional discussions.

Final Answer:
The set that lists only common basic network topologies is Star, Bus, Ring, Mesh.