Select the most appropriate one-word substitution for the given group of words.

Someone taken a prisoner to fulfil demands

hostage

The most appropriate one-word substitution for "someone taken a prisoner to fulfil demands" is hostage.

The other words in the options, dealer, host, and guest, do not mean the same thing.

• Dealer is a person who buys and sells goods or services.
• Host is a person who entertains guests in their home.
• Guest is a person who is invited to stay at someone else's home or to attend an event.

A hostage is a person who is held captive by another person or group in order to force the fulfillment of a demand. Hostages are often taken in order to secure the release of other prisoners, to obtain money, or to achieve political goals.