C#.NET — Set a constant value 3.14 for pi so it cannot be modified later: choose the correct construct.

Introduction / Context:
Constants in C# are compile-time values that cannot change after compilation. This question asks which syntax properly defines an immutable numeric constant.

Given Data / Assumptions:

• Desired value: 3.14 (float literal → use suffix F).
• Requirement: cannot be modified later.

Concept / Approach:
Use const for compile-time constants. A const must be assigned at declaration. #define in C# only defines a conditional compilation symbol, not a numeric macro as in C/C++.

Step-by-Step Solution:

Verification / Alternative check:
Attempting to reassign pi when declared const produces a compile-time error, proving immutability.

Why Other Options Are Wrong:
They either define mutable data or use invalid/unsupported syntax.

Common Pitfalls:
Confusing const with readonly (readonly allows assignment in constructor at run time; const is compile-time).

Final Answer:
const float pi = 3.14F;