The DetectLanguageAsync(String) method detects the language of a text. Incorrect Answers: A: the Spark natural language processing functionality on Azure HDInsight Doesn't support language detection. C: The RecognizeAsync method of the SpeechRecognizer object is used for speech recognition. D: The request URL to https://api.cognitive.microsoft.com/bing/v7.0/search is used for customized searches. References: https://docs.microsoft.com/en-us/dotnet/api/microsoft.toolkit.services.microsofttranslator.translatorservice.detectlanguageasync ?view=win-comm-toolkit-dotnet-stable