Final answer:
The IEEE specification related to NIC teaming is IEEE 802.3ad, which is known for Link Aggregation that groups multiple NICs to increase throughput and provide redundancy.
Step-by-step explanation:
The IEEE 802.3ad specification relates to NIC teaming, which is the process of grouping several network interface controllers (NICs) to work together as a team to provide redundancy and increased throughput. This technology is also known as Link Aggregation and was developed under the IEEE 802.3ad standard, which has since been absorbed into IEEE 802.1AX. None of the other options listed (IEEE 802.1Q, IEEE 802.11ac, IEEE 802.15.4) have a direct relationship with NIC teaming. IEEE 802.1Q pertains to VLAN tagging, IEEE 802.11ac is related to wireless networking, and IEEE 802.15.4 is associated with low-rate wireless personal area networks (LR-WPANs).
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