Questa, an online polling and research company maintains a panel of people living in the UK which it claims is demographically representative of the UK population. You are thinking of hiring them to generate a sample of primary quantitative data from a questionnaire you have designed and piloted. It proposes to offer you the first $350$ responses it receives from its panel.What type of sampling strategy is this?A$.$ RandomB. SnowballC. StratifiedD. Convenience