Gulshan grocer

Gulshan Grover is riding a bike at the velocity of light.
On the way he offers a lift to a stranger.
Stranger: "Sir, can I know your name please"
Gulshan: "I am Gulshan Grocer"
Stranger: "Grocer? Sure you dont mean Gulshan Grover??"
Gulshan: "No it is Grocer"
Now tell me why did Gulshan say so...
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Further…
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Little further...
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ANS: Because at the speed of light V=C