1st statement true since average of July is more than that of December in the Average plot
2nd statement - not true since, we have data till $95\%$ only -- in all data of $50$ years, amount of rainfall is below the value presented by graph in $95\%$ cases. So in the remaining $5\%$ of years, there can be a year where it rains more in January than August
3rd statement true- since difference between $5-\text{percentile}$ plot and $95-\text{percentile}$ plot indicates that this was range for $90\%$ of years. In February this range is bigger compared to July.
4th statement - not necessarily true. Here, the $5-\text{percentile}$ plot is touching $500mm$ level. But any year in this $5\%$ could have got a lower level of rainfall.
So, answer is $B.$