If, symbols - Practice Exercises C# Sharp

using System;
public class exercise065
{
    public static void Main()
    {
        char symbol;

        Console.Write("insert anything: ");
        symbol = Convert.ToChar(Console.ReadLine());

        if (symbol >= '0' && symbol <= '9')
            Console.WriteLine("it's a number");

        else if ((symbol == 'a') || (symbol == 'e') || (symbol == 'i')
                || (symbol == 'o') || (symbol == 'u'))
            Console.WriteLine("it's a lowercase vowel");

        else if ((symbol == 'A') || (symbol == 'E') || (symbol == 'I')
                || (symbol == 'O') || (symbol == 'U'))
            Console.WriteLine("it's a upercase vowel");

        else
            Console.WriteLine("it's a symbol");
    }
}