With reference to the C40 cities climate leadership group (C40), which of the following statements are correct?

1. C40 is a network of mayors of nearly 100 world-leading cities. 

2. C40’s mission is to halve the emissions of its member cities within a decade.

3. It operates on membership fees.

4. Four Indian cities are part of it.

5. It uses a science-based and collaborative approach to help the world limit global heating to 1.5°C 

Select the correct answer using the code given below.