Explanation:
To solve the expression \(81^{0.25} \times 81^{1.25} \times 81^{0.50}\), we can simplify by combining the exponents since the bases are the same:

1. Combine the exponents:
\[
81^{0.25} \times 81^{1.25} \times 81^{0.50} = 81^{(0.25 + 1.25 + 0.50)}
\]

2. Add the exponents:
\[
0.25 + 1.25 + 0.50 = 2.00
\]

3. Simplify the expression:
\[
81^{2.00} = 81^2
\]

4. Calculate \(81^2\):
\[
81^2 = 6561
\]

Thus, the value of the expression is \(6561\). The correct answer is:

C. 6561