The correct answer is option 1: Natural gas. During the period 2015-2016, the growth in production of natural gas in India was negative. This means that the production of natural gas decreased during this period.
It is important to understand that the growth in production is measured in percentage terms. A negative growth rate indicates a decline in production compared to the previous period. In this case, the growth rate of natural gas production was negative, suggesting a decrease in the overall production of natural gas during the specified period.
The other options - refinery products, fertilizer, and coal - do not specify whether their growth in production during the period 2015-2016 was positive or negative, so we cannot assume anything about their growth rates based on the information provided.
In summary, the growth in production of natural gas in India during the period 2015-2016 was negative, indicating a decrease in production compared to the previous period.