Explanation:

- The Duleep Trophy is a domestic first-class cricket competition in India. It is named after Kumar Shri Duleepsinhji.

- In September 2018, the Duleep Trophy final was played at NPR College Ground in Dindigul, Tamil Nadu.

- India Blue won the Duleep Trophy in 2018 by defeating India Red.

Options:

1. India Yellow – Not a participant in the 2018 final.

2. India Black – Not a participant in the 2018 final.

3. India Green – Not a participant in the 2018 final.

4. India Blue – This is the correct answer. They won the final against India Red.