C#.NET Generics — multiple constraints: reference type + interface. Given: public class MyContainer<T> where T : class, IComparable { // Insert code here } Which statements are valid? MyContainer requires that its type argument implement IComparable. The compiler will report an error for this block of code. There are multiple constraints on the type argument. The type argument must be a reference type and must implement IComparable.

Introduction / Context:
This item tests understanding of combining constraints in a C# generic type. Constraints can specify reference/value type requirements and required interfaces/base classes.

Given Data / Assumptions:

• Constraint list: where T : class, IComparable.
• class means T must be a reference type.
• IComparable means T must implement that interface.

Concept / Approach:
Multiple constraints are comma-separated. The presence of class is a reference-type constraint and IComparable is an interface constraint. This is valid syntax and compiles when IComparable is available.

Step-by-Step Solution:

Verification / Alternative check:
MyContainer<string> is valid (string is reference type and implements IComparable). MyContainer<int> is invalid (int is a value type).

Why Other Options Are Wrong:
Options including (2) claim a compilation error that does not occur. Options that omit (3) or (4) miss the essence of multiple constraints.

Common Pitfalls:
Assuming the presence of one constraint implies the other, or believing the comma means “either-or” (it is “and”).

Final Answer:
3 and 4 Only