FizzBuzz in C#

Program.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace FizzBuzz
{
    class Program
    {
        static void Main(string[] args)
        {
            // "Write a program that prints the numbers from 1 to 100. But for multiples of three print “Fizz” instead of the number and for the multiples of five print “Buzz”. For numbers which are multiples of both three and five print “FizzBuzz”."
            
            // for i from 1 to 100
            for (int i = 1; i <= 100; i++)
            {
                System.Console.WriteLine(FizzBuzz(i)); 
            }
            System.Console.WriteLine("Press any key to exit...");
            System.Console.ReadKey();
        }

        public static string FizzBuzz(int i)
        {
            if (i % 15 == 0)
            {
                return "FizzBuzz";
            }
            else if (i % 5 == 0)
            {
                return "Buzz";
            }
            else if (i % 3 == 0)
            {
                return "Fizz";
            }
            else
            {
                return i.ToString();
            }
        }

        public static string FizzBuzz1(int i)
        {
            StringBuilder sb = new StringBuilder();
            if (i % 3 == 0)
            {
                sb.Append("Fizz");
            }
            if (i % 5 == 0)
            {
                sb.Append("Buzz");
            }
            if (sb.Length == 0)
            {
                sb.Append(i);
            }
            return sb.ToString();
        }
    }
}