Evaluate (6/11×13×15)^xy: Complex Fraction with Variable Exponents

First, let's apply the exponent to the entire fraction:

$\left(\frac{6}{11 \times 13 \times 15}\right)^{xy} = \frac{6^{xy}}{(11 \times 13 \times 15)^{xy}}$

Now, distribute the $xy$ exponent in the denominator to each factor:

$\frac{6^{xy}}{11^{xy} \times 13^{xy} \times 15^{xy}}$

Thus, the rewritten expression is $\frac{6^{xy}}{11^{xy} \times 13^{xy} \times 15^{xy}}$.

Comparing our expression with the options given and based on our simplification, option 3: $\frac{6^{xy}}{\left(11 \times 13 \times 15\right)^{xy}}$ makes sense, as well as option 2: $\frac{6^{xy}}{11^{xy}\times13^{xy}\times15^{xy}}$ after distributing the exponent within the denominator.

Therefore, both options B and C are correct, making the right choice option 4.

Therefore, the correct answer is: B+C are correct.