<span>A shortcut is a used to quickly open a folder, data file, program, or other object. They are very convenient to have and make navigating through a computer extremely easy.</span>
The answer is B. A only. The optimum valve timing is found through experimentation using an engine dynamometer. The timing of the opening and closing of the valves is called valve timing. So the use of dynamometer measures the power output of a machine that is why it can measure the optimum valve timing.
Answer:A)Smart-card PINs
Explanation: A pin is the defines as the personal identification number that is allotted to the smart card uniquely that is no other smart can have same number.This number is only known by the smart card holder only.
This number is important because it works for the unlocking of the data that is securely stored and by entering the pin ,it can be decoded.Thus, the other given options are incorrect because they don't use enumeration to hide the data .Thus the correct option is option (A)
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