Question

select all examples of proper keyboarding technique. rest your fingers gently on the home row or home keys. slouch in your chair. rest your palms on the keyboard. relax your fingers. keep your hands lower than your elbows.

Answer 1

Rest your fingers gently on the home row is good proper
slouching is not
resting your palms is proper, though most teachers don't teach that.
Keeping your hands lower is not

Answer 2

Rest your fingers gently on the home row or home keys.

Rest your palms on the keyboard.

Relax your fingers.

All the above are proper keyboard techniques apart from slouch in your chair. It is always recommended to sit up straight with your feet positioned on the floor for balance. Do not cross. Center your body to the H key and have your elbows at sides and bent about 90 degrees. Use correct fingering and deploy touch typing. These and many others will help develop optimal speed and accuracy and help prevent the development of stress injury.