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#include <bits/stdc++.h>

const int MAX_N = 1e3;
const int base = 1<<12;

std::vector<int> list[MAX_N+3];
int n, m, k;
int best[MAX_N+3];
bool taken[MAX_N+3];
int deg[MAX_N+3];
int DEG_SUM;

std::pair<int, int> t[2*base+5];

void insert(int v, int x) {
    v += base;
    t[v] = {x, v-base};
    v /= 2;
    while (v > 0) {
        t[v] = std::max(t[v*2], t[v*2+1]);
        v /= 2;
    }
}

std::pair<int, int> get_max() {
    return t[1];
}

void disable(int v) {
    taken[v] = true;
    for (auto u : list[v]) 
        if (!taken[u]) { 
            deg[u]--; 
            deg[v]--;
            insert(u, deg[u]);
            DEG_SUM -= 2;
        }
    insert(v, deg[v]);
}

void enable(int v) {
    taken[v] = false;
    for (auto u : list[v]) 
        if (!taken[u]) { 
            deg[u]++; 
            deg[v]++;
            insert(u, deg[u]);
            DEG_SUM += 2;
        }
    insert(v, deg[v]);
}

bool visited[MAX_N+3];

int find_next(int v) {
    for (auto u : list[v]) if (!taken[u] && !visited[u]) return u;
    return -1;
}

int go_2() {
    for (int i = 1; i <= n; i++) visited[i] = false;
    int res = 0;

    for (int i = 1; i <= n; i++) {
        int u = i;
        if (deg[u] == 1 && !visited[u]) {
            int l = 1;
            visited[u] = true;
            while (1) {
                int v = find_next(u);
                if (v != -1) { l++; visited[v] = true; u = v; }
                else break;
            }
            res += l/2;
        }
    }

    for (int i = 1; i <= n; i++) {
        int u = i;
        if (deg[u] == 2 && !visited[u]) {
            int l = 1;
            visited[u] = true;
            while (1) {
                int v = find_next(u);
                if (v != -1) { l++; visited[v] = true; u = v; }
                else break;
            }
            if (l > 1)
                res += ((l+1)/2);
        }
    }
    return res;
}

int MIN_VC_FOUND;
int get_min_vc(int cnt_taken) {
    if (cnt_taken > MIN_VC_FOUND) return 99;
    if (cnt_taken > k) return 99;
    if (DEG_SUM == 0) { 
        MIN_VC_FOUND = std::min(MIN_VC_FOUND, cnt_taken);
        return cnt_taken;
    }
    if (cnt_taken >= k && DEG_SUM != 0) return 99;
    
    int v = get_max().second;
    int max_deg = get_max().first;

    if (max_deg == 1) {
        if (cnt_taken + (DEG_SUM/2) <= k) {
            MIN_VC_FOUND = std::min(MIN_VC_FOUND, cnt_taken + (DEG_SUM/2));
            return cnt_taken + (DEG_SUM/2);
        }
        return 99;
    } else if (max_deg == 2) {
        int res = go_2();
        if (cnt_taken + res <= k) {
            MIN_VC_FOUND = std::min(cnt_taken + res, MIN_VC_FOUND);
            return cnt_taken + res;
        }
        return 99;
    }

    // exclude v from VC, this means that his whole neighbourhood must be in VC
    std::vector<int> U;
    for (auto u : list[v]) 
        if (!taken[u]) { disable(u); U.push_back(u); }
    int res = get_min_vc(cnt_taken + U.size());
    for (auto u : U) enable(u);
    disable(v);
    res = std::min(res, get_min_vc(cnt_taken+1));
    enable(v);  
        
    return res;
}

void solve() {
    std::cin >> n >> m >> k;
    for (int i = 1; i <= n; i++) {
        list[i].clear();
        deg[i] = 0;
    }
    DEG_SUM = 0;

    std::set<std::pair<int, int> > edges;

    for (int i = 1; i <= m; i++) {
        int u, v; std::cin >> u >> v;
        if (edges.count({u,v}) || edges.count({v,u}))
            continue;
        edges.insert({u,v});
        list[u].push_back(v);
        list[v].push_back(u);
        deg[u]++;
        deg[v]++;
        DEG_SUM += 2;
    }

    for (int i = 1; i <= n; i++) insert(i, deg[i]);
    
    MIN_VC_FOUND = 100;
    for (int i = 1; i <= n; i++) {
        // min vc assuming i is taken
        disable(i);
        best[i] = get_min_vc(1);
        MIN_VC_FOUND = std::min(MIN_VC_FOUND, best[i]);
        enable(i);
    }

    if (MIN_VC_FOUND <= k) {
        std::cout << MIN_VC_FOUND << " ";
        int v_cnt = 0;
        for (int i = 1; i <= n; i++) if (best[i] == MIN_VC_FOUND) v_cnt++;
        std::cout << v_cnt << "\n";
        for (int i = 1; i <= n; i++) if (best[i] == MIN_VC_FOUND) std::cout << i << " ";
        std::cout << "\n";
    } else {
        std::cout << "-1\n";
    }

    for (int i = 1; i <= n; i++) insert(i, 0);
}

int main() {
    std::ios_base::sync_with_stdio(0); std::cin.tie(NULL);
    int t;
    std::cin >> t;
    while (t--)
        solve();   
}