802.3af: 15.4 watts. 802.3at (PoE+): 30 watts. 802.3bt (PoE++): up to 90 watts.

• A. 802.3af: 15.4 watts; 802.3at (PoE+): 30 watts; 802.3bt (PoE++): up to 90 watts
• B. 802.3af: 30 watts; 802.3at: 15.4 watts; 802.3bt: 60 watts
• C. PoE standards do not specify wattage.
• D. PoE cannot supply power over Ethernet.

Answer: (A)

Power over Ethernet defines how much power a PoE switch (PSE) can supply per port, and the standards increase those limits over time. 802.3af (PoE) provides up to 15.4 watts per port, though devices typically receive about 12.95 watts after cable losses. 802.3at (PoE+) raises that to about 30 watts per port to support more demanding devices. 802.3bt (PoE++) pushes further, with up to 60 watts per port in one enhancement and up to 90 watts per port in the strongest form, accommodating high-power equipment. The option matching these exact numbers is correct because it reflects the real power ceilings defined by each standard. The other choices misstate the wattages, claim wattage isn’t specified, or say PoE cannot supply power, which they do not align with how PoE is defined.