Question: An XML document contains this code as part of the DTD: . What are the rules that need to be followed for each of the elements?

1. is required, is optional, is optional, and is optional.
2. is required, is required, is optional, and is optional.
3. is required, is required, is required, and is optional.
4. is required, is optional, is required, and is optional.

Answer: The correct answer of the above question is Option D: is required, is optional, is required, and is optional.