In TDM, slots are further divided into

Concept

Time Division Multiplexing (TDM) organizes a shared channel's transmission time into a strict containment hierarchy: a TDM frame is divided into a fixed number of time slots (one slot per multiplexed input line), and under the standard synchronous-TDM convention, each individual slot carries a fixed-size unit of the sender's raw digital data — one or more bits. So the direction of division is always frame → slots → bits: a frame is the larger container, and bits are the smallest transmitted unit carried within a slot.

Application

The question asks what a slot is further divided into — that is, the level immediately below a slot in this hierarchy.

1. Frames sit above slots in the hierarchy (a frame is divided into slots, not the reverse), so a slot cannot be further divided into frames.

2. Packets belong to the network layer, a different layer of the protocol stack used for routing data across packet-switched networks — a TDM slot's payload is not generically split into packets.

3. That leaves bits: the fundamental, immediate unit of digital data a TDM slot carries, matching the standard TDM structure.

Cross-check

It is true that a frame's or packet's payload is, at the lowest possible level, also representable in bits — everything digital eventually reduces to bits. But the question is not asking what things are ultimately made of; it is asking what a slot is immediately divided into within the TDM hierarchy. Frames and packets are themselves higher-level constructs (represented using bits, not something a slot breaks down into), so treating that universal bit-representation as grounds for 'more than one of the above' confuses representation with the immediate structural level being asked about. Bits is the value that correctly completes this specific relationship, matching the exam's own official answer key for this question.