Which of the following, when enabled on all devices, will decrease the number of packets sent on the network?

Class of Service (CoS) is a mechanism for classifying and prioritizing network traffic, not for reducing the number of packets.

Jumbo Frames are Ethernet frames that are larger than the standard 1500-byte Maximum Transmission Unit (MTU). By increasing the MTU, each frame can carry more data, consequently reducing the total number of frames (packets) required to transmit a given amount of data over the network, thereby decreasing processing overhead for network devices.

Quality of Service (QoS) is a set of technologies that manage network resources to provide preferential treatment to certain types of traffic; it does not inherently decrease the number of packets.

Link Aggregation (LAG) bundles multiple physical network links into a single logical link for increased bandwidth and redundancy, but it does not reduce the number of individual packets sent.