Which of the following has the best penetration through physical objects, such as walls?

2.4GHz Wi-Fi signals have better penetration through walls and other obstacles compared to 5GHz and 6GHz. Lower frequency waves (like 2.4GHz) travel farther and are less absorbed by physical barriers.

From the CompTIA A+ 220-1101 Official Study Guide, Objective 2.5 – Compare and contrast wireless networking protocols:

“The 2.4GHz frequency band offers greater range and better penetration through walls and obstacles than higher frequencies like 5GHz and 6GHz. Higher frequencies provide faster speeds but are more easily absorbed by walls.”

NFC (Near Field Communication) is not a Wi-Fi technology and works only over very short distances (a few centimeters).

Verified Source:

CompTIA A+ Core 1 (220-1101) Official Study Guide, Chapter 2: Wireless Networking

CompTIA Exam Objectives 220-1101, Domain 2.5

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