Answer: secondary consumer
Explanation:
Well first off they are commonly used for special needs. "<span>What appears as simple as a button, the proper switch will open up worlds of access to communication devices, environmental controls, computer software and mobile devices".</span>
Refrence:https://www.especialneeds.com/shop/assistive-technology/switches.html
The most common family type in Chinese cities was once the nuclear family. ... Covering more than 1,000 households in Beijing, Shanghai, Guangzhou and Wuhan, the survey found that the number of DINKs, one-person and linear or generational families are on the rise from six years ago.