To determine how many months had no thunderstorms, you would need to refer to the bar graph you're mentioning. Since I can't see the graph, I can't provide a specific answer.
However, you can easily find the answer by looking at the months represented on the graph. Count the number of months that have a bar height of zero. The correct number of months with no thunderstorms will be one of the options you provided: 8, 7, 3, or 4.
If you see 0 days marked for any months, count them to get the total number of months with no thunderstorms.
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