The question is asking for the square root of 64.

The square root of 64 is 8, since 8 × 8 = 64.

So, the correct answer is 8.

Would you like further details on how to calculate square roots or have any other questions?

Here are 5 related questions you might find helpful:

1. How do you find the square root of a number that is not a perfect square?
2. What is the difference between the square root and cube root of a number?
3. How do you simplify square roots for non-perfect squares?
4. What is the square root of 81?
5. How can you use a calculator to find square roots efficiently?

Tip: Remember that the square root of a positive number always has two answers, one positive and one negative. For example, the square roots of 64 are both 8 and -8, but typically, we refer to the principal (positive) square root when we say "square root."