Answer:
√37
Explanation:
It is helpful to know the squares of small integers. Then you become aware of the approximate magnitudes of square roots.
Point C is between 6 and 7, so the value of C² will be between 6² = 36 and 7² = 49. Since C is closer to 6 than to 7, it represents the root of a number closer to 36 than to 49.
Only one answer choice is in this range: √37, Option 1.