\[ 4 \times\left(3^{4}\right)\left(3^{5}\right)= \] A \( 3^{9} \) B \( 9^{9} \) C \( 3^{20} \) D \( 6^{20} \)

First, let's simplify the expression step-by-step. According to the properties of exponents, \( 3^4 \times 3^5 = 3^{4+5} = 3^9 \). Therefore, the expression becomes \( 4 \times 3^9 \). Next, looking at the options, we see that none of them directly match this form, but the option A \( 3^9 \) does appear as a component. So, the answer is that \( 4 \times 3^{4} \times 3^{5} \) simplifies down to \( 4 \times 3^9 \), which indicates none of the provided options are fully correct; nonetheless, the key takeaway is recognizing how to manipulate exponents effectively! As you tackle similar problems, remember that knowing exponent rules can lead to quick simplifications and clearer results! Also, be sure to double-check your options; sometimes they might not directly reflect your interim results, as in this case.