What can you say about the following statements? I. XML tags are case-insensitive. II. In JavaScript, identifier names are case-sensitive. III. Cascading Style Sheets (CSS) cannot be used with XML. IV. All well-formed XML documents must contain a document type definition. (1) only I and II are false. (2) only III and IV are false. (3) only I and III are false. (4) only II and IV are false.