Step 1: Understanding the Concept:
The decomposition of hydrogen peroxide is first order, and the half-life of a first-order reaction does not depend on concentration.
Step 2: Key Formula:
\[ t_{1/2} = \frac{0.693}{k} \]
Step 3: Calculation:
\[ t_{1/2} = \frac{0.693}{0.0204\ \text{min}^{-1}} = 33.97\ \text{min} \]
Step 4: Check the Other Options:
17.56 min would need \(k = 0.0395\), 51.50 min would need \(k = 0.01346\), and 68.70 min would need \(k=0.0101\). Since the given \(k\) is 0.0204, only 33.97 min is consistent. Option (B) is correct.
Final Answer:
The half-life is 33.97 min, option (B).
\[ \boxed{\text{(B) } 33.97\ \text{min}} \]