#include<bits/stdc++.h>
using namespace std;
#define fast ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define dbg(a,b,c,d) cerr<<a<<"  "<<b<<"  "<<c<<"  "<<d<<endl;
#define kill(a) {cout<<a<<endl;continue;}
#define KILL(a) {cout<<a<<endl;return 0;}
#define debug cerr<<"Error Found"<<endl;
#define mem(a,b) memset(a,b,sizeof(a))
#define lcm(a, b) (a/__gcd(a,b))*b
#define w(t) cin>>t;while(t--)
#define pi  2 * acos(0.0)
#define endl "\n"
int t, cs = 0;
const int mxn = 1e5 + 3, mod = 1e9 + 7;

int32_t main()
{
   fast;
    w(t)
    {
        int n, x;
        cin >> n >> x;
        map<int,int>freq;
        int mx = 0;
        for(int i = 0, a; i < n; i++)cin >> a, freq[a]++, mx = max(mx, a);
        int last = min(x, mx + 1);
        int mn = n + 1, K;
        for(int i = 1; i <= last; i++)
        {
            int cnt = 0;
            for(int j = i; j <= last; j += i)
            {
                cnt += freq[j];
            }
            if(cnt < mn)mn = cnt, K = i;
        }
        cout << K << endl;
    }
}