Introduction:
The Laplace transform is a mathematical tool used to analyze linear time-invariant systems, especially in the field of electrical engineering. It has various applications in circuit analysis, control systems, signal processing, and more. The Laplace transform allows us to transform a time-domain function into the frequency-domain, making it easier to analyze the system's behavior.

Explanation:
When we apply the Laplace transform to a system, we usually assume that the initial conditions are zero. This means that at the beginning of the analysis, the system is assumed to have no stored energy or any initial response. Therefore, the correct answer to the given question is option 'B' - "Initial conditions zero."

Reasoning:
The Laplace transform is particularly useful for systems with zero initial conditions because it simplifies the analysis and calculations. When the initial conditions are zero, the Laplace transform of the system's output is solely determined by the Laplace transform of the input signal and the system's transfer function.

Key Points:
- The Laplace transform is used for systems with zero initial conditions.
- Zero initial conditions imply that the system has no stored energy or initial response at the beginning of the analysis.
- The Laplace transform simplifies the analysis and calculations for systems with zero initial conditions.
- The Laplace transform of the output is solely determined by the Laplace transform of the input signal and the system's transfer function when the initial conditions are zero.

Conclusion:
In summary, the Laplace transform is used for systems with zero initial conditions. This assumption allows for a simplified analysis and calculation process. The Laplace transform of the output is solely determined by the Laplace transform of the input signal and the system's transfer function when the initial conditions are zero.