Calculate the decay constant (lambda) for a radioactive substance with a half-life of 2 minutes.

The given half-life ($T_{1/2}$) is 2 minutes.

$$T_{1/2} = 2 \, \text{minutes} \times \frac{60 \, \text{seconds}}{1 \, \text{minute}} = 120 \, \text{s}$$

The relationship between the half-life ($T_{1/2}$) and the decay constant ($\lambda$) is given by:

$$T_{1/2} = \frac{\ln(2)}{\lambda}$$

We know that $\ln(2) \approx 0.693$.

$$\lambda = \frac{0.693}{120 \, \text{s}}$$ $$\lambda \approx 0.005775 \, \text{s}^{-1}$$

$$\lambda \approx 5.775 \times 10^{-3} \, \text{s}^{-1}$$

Rounding to two significant figures, we get:

$$\lambda \approx 5.8 \times 10^{-3} \, \text{s}^{-1}$$

This matches option D.

The decay constant is \boxed{\text{5.8 \times 10^{-3} s^{-1}}}.