GCD Returns

You are given array of $n$ element and one integer $x$ $(x \le n)$. you have to select $x$ elements form array such that GCD of selected $x$ element is maximize. ###Input: - First line of input in number of testcases $t$ $(1 \le t \le 10)$. - First line of each testcase contain two integer $n$ and $x$ $(1 \le x \le n \le 10^5)$. - Second line of each testcase contain array of $n$ elements