To convert the repeating decimal \(0.27\) (where \(27\) repeats) into a rational number, let us denote it as \(x\):
\[ x = 0.27272727\ldots \]
Next, we can multiply both sides by \(100\) to shift the decimal point two places to the right:
\[ 100x = 27.27272727\ldots \]
Now, we can set up a second equation with just \(x\):
\[ x = 0.27272727\ldots \]
Now, we'll subtract the first equation from the second:
\[ 100x - x = 27.27272727\ldots - 0.27272727\ldots \]
This simplifies to:
\[ 99x = 27 \]
Now, we solve for \(x\):
\[ x = \frac{27}{99} \]
Next, we simplify \(\frac{27}{99}\). The greatest common divisor (GCD) of \(27\) and \(99\) is \(9\):
\[ x = \frac{27 \div 9}{99 \div 9} = \frac{3}{11} \]
Thus, \(0.27\) (repeating) as a rational number in simplest form is:
\[ \boxed{\frac{3}{11}} \]
Therefore, the correct answer is B. \( \frac{3}{11} \).