Answer:
The correct choice is C
Explanation A:
Shock Absorbers are best replaced in pairs if the car is relatively old. For new cars, however, one may elect to do the replacements as the need arises given that the other part is not worn out yet.
Explanation B:
It also recommended to bleed shock absorbers by moving the piston rod up and down several times. The reason is that sometimes, whilst in a horizontal position the hydraulic fluid and the gas get mixed up. This dampens the ability of the device to absorb shocks until the vehicle has been bounced up and down several times.
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