#include <bits/stdc++.h>
using namespace std;

#define all(x) begin(x), end(x)
#ifdef CKISEKI
#define safe cerr << __PRETTY_FUNCTION__ << " line " << __LINE__ << " safe\n"
#define debug(a...) debug_(#a, a)
#define orange(a...) orange_(#a, a)
template <typename ...T>
void debug_(const char *s, T ...a) {
    cerr << "\e[1;32m(" << s << ") = (";
    int cnt = sizeof...(T);
    (..., (cerr << a << (--cnt ? ", " : ")\e[0m\n")));
}
template <typename I>
void orange_(const char *s, I L, I R) {
    cerr << "\e[1;32m[ " << s << " ] = [ ";
    for (int f = 0; L != R; L++)
        cerr << (f++ ? ", " : "") << *L;
    cerr << " ]\e[0m\n";
}
#else 
#define safe ((void)0)
#define debug(...) safe
#define orange(...) safe
#endif

namespace {

constexpr int kN = 35000 + 5;
constexpr int kMod = 1'000'000'007;
constexpr int kD = 1 << 5;

constexpr int add(int a, int b) {
    return a + b >= kMod ? a + b - kMod : a + b;
}
constexpr int mul(int64_t a, int64_t b) {
    return static_cast<int>(a * b % kMod);
}

int a[kN];
vector<int> g[kN];

void pre(int u, int f) {
    vector<int> cur;
    for (int v : g[u]) {
        if (v == f)
            continue;
        cur.push_back(v);
        pre(v, u);
    }
    g[u] = cur;
}

int sm[kN][kD];
int dp[kN][kD + 1];
bool bad[kN][kD];

int dfs(int u) {
    const int d = int(g[u].size());
    const int d2 = 1 << d;
    sm[u][0] = 1;
    for (int S = 1; S < d2; ++S) {
        sm[u][S] = a[u];
        for (int i = 0; i < d; ++i) {
            if ((S >> i) & 1) {
                sm[u][S] += a[g[u][i]];
                bad[u][S] |= bad[u][S ^ (1 << i)];
            }
        }
        if (sm[u][S] > 0)
            bad[u][S] = true;
    }

    dp[u][kD] = 1;
    for (int v : g[u]) {
        dp[u][kD] = mul(dp[u][kD], dfs(v));
    }
    vector<int> tot(g[u].size(), 1);
    for (int i = 0; i < d; ++i) {
        const int v = g[u][i];
        const int vd2 = 1 << int(g[v].size());
        for (int j = 0; j < vd2; ++j) {
            if (bad[v][j])
                continue;
            if (sm[v][j] + a[u] > 0)
                continue;
            tot[i] = add(tot[i], dp[v][j]);
        }
    }
    int ret = dp[u][kD];
    for (int S = 0; S < d2; ++S) {
        if (bad[u][S])
            continue;
        dp[u][S] = 1;
        for (int j = 0; j < d; ++j)
            if ((S >> j) & 1)
                dp[u][S] = mul(dp[u][S], tot[j]);
            else
                dp[u][S] = mul(dp[u][S], dp[g[u][j]][kD]);
        ret = add(ret, dp[u][S]);
    }
    return ret;
}

} // namespace

int main() {
    cin.tie(nullptr)->sync_with_stdio(false);
    int t;
    cin >> t;
    while (t--) {
        int n, x;
        cin >> n >> x;
        for (int i = 0; i < n; ++i) {
            cin >> a[i];
            a[i] -= x;
        }
        for (int i = 1; i < n; ++i) {
            int u, v;
            cin >> u >> v;
            u -= 1, v -= 1;
            g[u].push_back(v);
            g[v].push_back(u);
        }
        pre(0, 0);
        cout << dfs(0) << '\n';
        for (int i = 0; i < n; ++i) {
            memset(dp[i], 0, sizeof(dp[i]));
            memset(sm[i], 0, sizeof(sm[i]));
            memset(bad[i], 0, sizeof(bad[i]));
            g[i].clear();
        }
    }
    return 0;
}
/*
1
5 0
1 1 1 1 1
1 2
2 3
3 4
4 5
bad[0][1] = true (2)
bad[1][1] = true (2)
bad[2][1] = true (2)
bad[3][1] = true (2)
dp[4][No] = 1
dp[3][No] = 2
dp[3][1] = 0
dp[2][No] = 3
dp[2][1] = 0
dp[1][No] = 4
dp[1][1] = 0
dp[0][No] = 5
dp[0][1] = 0
6
*/