#include <cstdio>
#include <algorithm>
#include <vector>
#include <cstring>
#include <numeric>
#include <cassert>
#include <cmath>
using namespace std;
typedef unsigned int uint;
typedef unsigned long long LL;

#define FOR(k,a,b) for(uint k(a); k < (b); ++k)
#define REP(k,a) for(uint k=0; k < (a); ++k)

const int MOD = 1e9 + 7;

LL invmod(LL a)
{
	int p = MOD-2;
	LL res = 1;
	a %= MOD;
	while(p)
	{
		if(p&1)
		{
			res *= a;
			res %= MOD;
		}
		a *= a;
		a %= MOD;
		p >>= 1;
	}
	return res;
}

LL calc(int n,int x,LL m, const vector<int>& v)
{
	LL res = 0, tmp;
	--m;
	int u = m%MOD, d = 0;
	LL act = 1;
	REP(i,x)
	{
		tmp = act * v[x-1-i];
		tmp %= MOD;
		res += tmp;
		if (res >= MOD) res -= MOD;
		if(d<m)
		{
			act *= u+1;
			act %= MOD;
			act *= invmod(d+1);
			act %= MOD;
			++u;
			++d;
		}
		else
		{
			act *= u+1;
			act %= MOD;
			act *= invmod(u+1-d);
			act %= MOD;
			++u;
		}
		
	}
	return res;
}

int main (int argc, char** argv) {
#ifdef HOME
	freopen("in.txt","rb",stdin);
	freopen("out.txt","wb",stdout);
#endif
	int T,n,x;
	LL m, tmp, res;
	vector<int> v;
	scanf("%d",&T);
	assert(T>0 && T<11);
	while(T--)
	{
		scanf("%d %d %lld",&n,&x,&m);
		assert(0<x && x<=n && n<=1e5);
		assert(0<m && m<=1e18);
		v.resize(n);
		REP(i,n)
		{
			scanf("%lld",&tmp);
			assert(tmp>0 && tmp<=1e18);
			tmp%=MOD;
			v[i]=tmp;
		}
		res = calc(n,x,m,v);
		printf("%lld\n",res);
	}
	return 0;
}