The correct answer is B. Packet switching.
Circuit switching is a type of data communication in which a dedicated circuit is established between the sender and receiver for the duration of the communication. This type of communication is ideal for applications that require a constant, reliable connection, such as telephone calls. However, it is not ideal for applications that generate small amounts of data, as the time required to establish the circuit can be significant compared to the amount of data being transmitted.
Packet switching is a type of data communication in which data is broken up into small packets, which are then routed independently through the network to the destination. This type of communication is more efficient than circuit switching for applications that generate small amounts of data, as the packets can be transmitted as soon as they are ready, without waiting for a dedicated circuit to be established.
Time division multiplexing (TDM) is a technique used to share a single communication channel among multiple users. This is done by dividing the channel into time slots, which are then assigned to each user in turn. This type of communication is efficient for applications that generate data at a constant rate, as each user can be allocated a time slot for the duration of their transmission.
In the case where the time to establish link is large and the size of data is small, the preferred mode of data transfer is packet switching. This is because packet switching is more efficient for applications that generate small amounts of data, as the packets can be transmitted as soon as they are ready, without waiting for a dedicated circuit to be established.