Ideally, the backrest is tilted back slightly, so when you turn the wheel your shoulders are the seat. a. not touching b. touching c. parallel with d. horizontal to

The backrest should be tilted slightly back, so when turning the steering your shoulders are touching the seat.

Backrest is either a chair or seat where you rest your back. The primary function of a backrest is to help the lumbar lordosis ( the lumbar lordosis is an inward curve of the lumbar or spine in the back of the human body, it is advisable in little degree and it's a danger when it's excessive).

The backrest should be tilted slightly back so the shoulders are always touching the seat, when the shoulders rarely touch the seat, it could lead to discomfort on the back and possible health issues.

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b)touching

Explanation:

The backrest of the seat should be tilted back ever so slightly, and when turning the steering wheel your shoulders should remain in contact with the seat – rather than hunched forward.