Https://mathbitsnotebook.com/Algebra1/RealNumbers/RNProp.html
C is the answer !!!!!!!!!
The square root of 71 is equal to 8.426149773176359...., which is between 8 and 9.
To check: square of 8 is 64, and of 9 is 81: 71 is between those two numbers, as it should be.