Recruiters and Hiring managers will be able to restrict Programming languages.
Login to your WeCP account as a Recruiter or Hiring Manager.
Navigate to the test which has the programming questions and click on the Questions tab.
Select the question you want to restrict the language on and click on the "Edit Question" button on the top right.
Click on Programming languages and turn Restrict Languages on
You will be presented with a number of languages from which to choose the best ones for you.