Question: CSS grid introduced a new length unit, fr, to create flexible grid tracks. Referring to the code sample below, what will the widths of the three columns be?

1. The first column will have a width of 50px. The second column will be 50px wide and the third column will be 100px wide.
2. The first column will have a width of 50px. The second column will be 150px wide and the third column will be 300px wide.
3. The first column will have a width of 50px. The second column will be 300px wide and the third column will be 150px wide.
4. The first column will have a width of 50px. The second column will be 500px wide and the third column will be 1000px wide.

Answer: The correct answer of the above question is Option B:The first column will have a width of 50px. The second column will be 150px wide and the third column will be 300px wide.