Which subscription-based language learning company was the first to reach a $1 billion valuation, becoming the language industry's first 'unicorn' in 2015?

Language learning and linguistic tools have undergone massive changes in their business models over the past decade. Traditional one-time purchases of dictionaries and language courses have largely given way to subscription-based services with regular updates and expanded features. This poll tests your knowledge of how subscription models have specifically transformed the language learning and linguistics industry.

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Duolingo
Babbel
Rosetta Stone
Memrise