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CSharp · Console

/Program.cs

using System;
using System.Collections.Generic;
using System.Linq;
using Newtonsoft.Json;					

public class Program
{
	public static void Main()
	{		
		List<string> list1 = new List<string> { "test", "otherTest" };
		List<string> list2 = new List<string> { "item", "otherItem" };
		List<string> list3 = new List<string> { "value", "otherValue" };

		var list = new List<List<string>>() { list1, list2, list3 }
			.Aggregate(
				seed: Enumerable.Range(0, list1.Count).Select(e => new List<string>()),
				func: (prev, next) => prev.Zip(next, (first, second) => { first.Add(second); return first; })
			)
			.Select(e => new
			{
				a = e.ElementAt(0),
				b = e.ElementAt(1),
				c = e.ElementAt(2)
			});
			
		Console.WriteLine(JsonConvert.SerializeObject(list, Formatting.Indented));
	}
}