linq查詢的等效lambda語法

Question

我在這里有一個心靈凍結，但我似乎無法找到等效的lambda語法 -

string[] a = {"a","b","c"}; 
string[] b = {"1","2","3"}; 

var x = from a1 in a
        from b1 in b
        select new{a1, b1};

Answer 1

var x = a.SelectMany(a1=>b.Select(b1=>new {a1,b1}));

Answer 2

ReSharper說：

var x = a.SelectMany(a1 => b, (a1, b1) => new { a1, b1 });