Step 1: Using the de Broglie wavelength formula.
The de Broglie wavelength \( \lambda \) is given by:
\[
\lambda = \frac{h}{mv}
\]
where:
- \( h = 6.63 \times 10^{-34} \, \text{Js} \) (Planck's constant),
- \( m = 0.033 \, \text{kg} \) (mass of the object),
- \( v = 1 \, \text{km/s} = 1000 \, \text{m/s} \) (velocity of the object).
Step 2: Substituting values into the formula.
Substitute the given values into the formula:
\[
\lambda = \frac{6.63 \times 10^{-34}}{0.033 \times 1000} = 2 \times 10^{-35} \, \text{m}
\]
Step 3: Conclusion.
The de Broglie wavelength is \( 2 \times 10^{-35} \, \text{m} \), so the correct answer is (C).