Answer: A) Turnitin
Step-by-step explanation:
Turnitin is the website that offers a good opportunity for checking the proper citation and once the information or paper is submitted and store store in this website then, it becomes its database permanently.
It basically determine that whether the uploaded paper is original or not. The turnitin website identify the pre-phases in the document or paper. It does not accept any kind of PDF file, forms and portfolios.
All of the other given options are that particular website which determine the originality of the paper.