What is a valid output?

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Question $21$ options:

$1$ Kilometer $=1000$ Meter or $1$ Kilometer is equal to $1000$ Meter

$1$ Litre $=1000$ Millilitre or $1$ Litre is equal to $1000$ Millilitre

$1$ Kilojoule $=1000$ Joule or $1$ Kilojoule is equal to $1000$ Joule

$1$ Kilometer $=1000$ Meter or $1$ Kilometer is equal to $1000$ Meter

$1$ Kilojoule $=1000$ Joule or $1$ Kilojoule is equal to $1000$ Joule

$1$ Litre $=1000$ Millilitre or $1$ Litre is equal to $1000$ Millilitre

$1$ Ton $=1000$ Kilograms or $1$ Ton is equal to $1000$ Kilograms

$1$ Meter $=1000$ Kilometer or $1$ Meter is equal to $1000$ Kilometer

$1$ Joule $=1000$ Kilojoule or $1$ Joule is equal to $1000$ Kilojoule

$1$ Millilitre $=1000$ Litre or $1$ Millilitre is equal to $1000$ Litre

$1$ Meter $=1000$ Kilometer or $1$ Meter is equal to $1000$ Kilometer

$1$ Joule $=1000$ Kilojoule or $1$ Joule is equal to $1000$ Kilojoule

$1$ Millilitre $=1000$ Litre or $1$ Millilitre is equal to $1000$ Litre

$1$ Kilograms $=1000$ Ton or $1$ Kilograms is equal to $1000$ Ton