The correct answer is (d) Switches and routers along the network add delays to the signal. This delay is mainly due to network latency and packet handling at multiple intermediate devices on the path between you, the Zoom servers, and the other participant.​​

Introduction (SEO‑optimized)

Experiencing an annoying delay in voice on Zoom calls is very common in online meetings. This delay is primarily caused by network latency introduced by switches, routers, and long internet paths, not by Zoom “waiting” for entire sentences or simply “slowing down” your computer. Understanding which factors are real and which are misconceptions helps in both solving the problem and answering exam-style multiple‑choice questions correctly.​

Option (a): Delay due to US Zoom data server

Statement: There is a delay when the signal is transmitted to the Zoom data‑server in the US, and then to the other computer.

• Data in a Zoom call does travel from your computer to a Zoom server (often in a remote data center) and then to the other participant, and this physical distance does contribute to latency.​

• However, this option oversimplifies the cause and attributes the delay solely to the server’s location, ignoring the many intermediate devices (routers, switches) and queuing delays on each hop that are the dominant contributors to end‑to‑end lag.​

Verdict: This option is partially true but incomplete, and in a conceptual MCQ the more accurate technical cause is expressed in option (d), not (a).

Option (b): Zoom slows down your computer

Statement: Zoom consumes a lot of computer time and so it slows down your computer.

• Zoom can use significant CPU and GPU resources, especially with HD video, virtual backgrounds, and gallery view, and high CPU load can cause choppy or out‑of‑sync audio/video on some systems.​

• Even so, this mostly affects quality (stutter, dropped frames, glitches) rather than creating a consistent one‑way propagation delay in the voice stream itself; basic network latency is still determined by the path and devices between endpoints, not just CPU usage.​

Verdict: CPU load can worsen call quality but is not the fundamental reason for the classic “annoying delay” described; hence option (b) is not the best answer.

Option (c): Network stores a long sentence before forwarding

Statement: Your network bandwidth is poor, so it stores a long sentence before forwarding it to the next machine.

• Real‑time systems like Zoom send audio as a continuous stream of small packets, not as complete “sentences”; they use small jitter buffers to smooth variation in packet arrival time, but these buffers are on the order of milliseconds, not entire spoken sentences.​

• Poor bandwidth and congestion can cause packet loss, jitter, and buffering, which may lead to brief freezes or robotic sound, but networks do not deliberately store an entire sentence before forwarding; that description is technically incorrect.​

Verdict: This is a misconception about how real‑time audio works over IP networks, so option (c) is incorrect.

Option (d): Switches and routers add delays (correct)

Statement: Switches and routers along the network adds delays to the signal.

• Every packet of your voice passes through multiple switches and routers, each introducing processing time, queuing delay, and sometimes additional delay from congestion, collectively called network latency.​

• Over long paths and busy networks, the cumulative delay from these devices, plus the distance to the Zoom server, produces the noticeable audio lag experienced during Zoom calls.​

Verdict: This option correctly captures the fundamental technical cause of the annoying delay in voice on Zoom calls, so (d) is the correct answer.