You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
New_Delhi

Context:
In 2010, Indira Gandhi International Airport (IGIA) was conferred the fourth best airport award in the world in the 15–25 million category, and Best Improved Airport in the Asia-Pacific Region by Airports Council International. The airport was rated as the Best airport in the world in the 25–40 million passengers category in 2015, by Airports Council International.[not in citation given][better source needed] Delhi Airport also bags two awards for The Best Airport in Central Asia/India and Best Airport Staff in Central Asia/India at the Skytrax World Airport Awards 2015.

Question:
In 2015, the Airports Council International gave what award to Indira Gandhi International Airport?

Best airport in the world in the 25–40 million passengers category