Hobson's choice
idiom

- a situation in which it seems that you can choose between different things or actions, but there is really only one thing that you can take or do

(Cambridge Advanced Learner's Dictionary)

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WORD ORIGIN

Thomas Hobson was a historical 16th/17th century figure who ran a prosperous delivery and horse rental business in Cambridge, England. Many of his customers were young undergraduate students who habitually treated the horses badly and drove them to exhaustion. He instructed the students, often in vain, that they would get to London from Cambridge just as fast if they would resist the urge to push the horse too hard.

In order to give the horses time to recover, Hobson implemented a rotation system. The horse most recently returned would be placed at the back of the stable. Customers were required to take the next one available at the front of the queue. There were no exceptions to this rule. If the customer didn't like the horse being offered, he would be told to take his business elsewhere. In the end, a Hobson's choice was no choice at all.

A well-known application of Hobson's choice was Henry Ford's offer of the Model-T car in "You can have any colour you like, so long as it's black."