Provide an example of code execution that returns an object of the IQueryable interface.

using System;
using System.Collections.Generic;
using System.Linq;

public class Product
{
    public int Id { get; set; }
    public string Name { get; set; }
    public decimal Price { get; set; }
}

public static class ProductService
{
    public static IQueryable<Product> GetProducts()
    {
        // Simulate a data source, e.g., a database
        // In a real application, this could be a DbSet from Entity Framework
        var products = new List<Product>
        {
            new Product { Id = 1, Name = "Laptop", Price = 1200.00m },
            new Product { Id = 2, Name = "Mouse", Price = 25.00m },
            new Product { Id = 3, Name = "Keyboard", Price = 75.00m },
            new Product { Id = 4, Name = "Monitor", Price = 300.00m },
        }.AsQueryable(); // Convert IEnumerable to IQueryable

        return products;
    }

    public static void Main(string[] args)
    {
        // Get IQueryable
        IQueryable<Product> queryableProducts = GetProducts();

        // Add filtering and sorting, which will be executed LAZILY
        // during data materialization (e.g., when calling ToList() or foreach)
        var expensiveProducts = queryableProducts
            .Where(p => p.Price > 100m)
            .OrderBy(p => p.Name);

        // At this point, the query has not been executed yet.
        Console.WriteLine("Query formed, but not yet executed.");

        // Data materialization - executing the query against the source
        Console.WriteLine("Executing query:");
        foreach (var product in expensiveProducts)
        {
            Console.WriteLine($"- Id: {product.Id}, Name: {product.Name}, Price: {product.Price:C2}");
        }

        // Example of another materialization
        var productList = expensiveProducts.ToList(); // Query executes again if not cached
        Console.WriteLine($"\nNumber of expensive products: {productList.Count}");
    }
}