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// 2022-3-med-medrcy-brut.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include <iostream>
#include <vector>
#include <set>
#include <algorithm>

constexpr int MAXN = 1e4;

std::set<int> edges[MAXN];

std::set<int> not_single;

std::set<int> good_vertices;

bool visited[MAXN];

void dfs1(int v) {
	visited[v] = 1;
	for (auto u : edges[v]) {
		if (!visited[u]) {
			dfs1(u);
		}
	}
}

int how_many_components() {
	int how_many = 0;
	for (auto u : not_single) {
		if (!visited[u]) {
			how_many++;
			dfs1(u);
		}
	}
	for (auto u : not_single) {
		visited[u] = 0;
	}
	return how_many;
}

int minimum_val(int max_val);

int handle_vertex(int max_val, int v) {
	std::set<int> ev = edges[v];
	not_single.erase(v);

	// edges[v].clear();

	for (auto u : ev) {
		edges[u].erase(v);
		if (edges[u].size() == 0) {
			not_single.erase(u);
		}
	}

	bool was_found = false;

	// the vertex is not taken
	if (max_val >= ev.size()) {
		for (auto u : ev) {
			for (auto w : edges[u]) {
				edges[w].erase(u);
				if (edges[w].size() == 0) {
					not_single.erase(w);
				}
			}
			not_single.erase(u);
		}

		int tmp1 = minimum_val(max_val - ev.size());
		if (tmp1 != -1) {
			was_found = 1;
			max_val = tmp1 + ev.size();
			good_vertices.insert(ev.begin(), ev.end());
		}

		for (auto u : ev) {
			for (auto w : edges[u]) {
				edges[w].insert(u);
				if (edges[w].size() > 0) {
					not_single.insert(w);
				}
			}
			if (edges[u].size() > 0) {
				not_single.insert(u);
			}
		}
	}

	// the vertex is taken
	int tmp1 = minimum_val(max_val - 1);
	if (tmp1 != -1) {
		was_found = true;
		max_val = tmp1 + 1;
		good_vertices.insert(v);
	}

	for (auto u : ev) {
		edges[u].insert(v);
		not_single.insert(u);
	}

	not_single.insert(v);
	if (!was_found) {
		return -1;
	}
	return max_val;
}

int minimum_val(int max_val) {
	if (not_single.empty()) {
		if (max_val > 0) {
			good_vertices.clear();
		}
		return 0;
	}
	if (max_val <= 0) {
		return -1;
	}
	if (how_many_components() > max_val) {
		return -1;
	}
	size_t mx_deg = 0;
	for (auto u : not_single) {
		mx_deg = std::max(mx_deg, edges[u].size());
	}
	for (auto u : not_single) {
		if (mx_deg == edges[u].size()) {
			return handle_vertex(max_val, u);
		}
	}
}

int main()
{
	int qqq, n, m, k, u, v, res;
	std::cin >> qqq;
	while (qqq--) {
		std::cin >> n >> m >> k;

		for (int i = 0; i <= n; i++) {
			edges[i].clear();
		}
		good_vertices.clear();
		not_single.clear();
		for (int i = 0; i < m; i++) {
			std::cin >> u >> v;
			edges[u].insert(v);
			edges[v].insert(u);
			not_single.insert(u);
			not_single.insert(v);
		}

		res = minimum_val(k);
		if (res == -1) {
			std::cout << "-1\n";
			continue;
		}
		std::cout << res << ' ' << good_vertices.size() << '\n';
		for (auto v : good_vertices) {
			std::cout << v << ' ';
		}
		std::cout << '\n';
	}
}

// Run program: Ctrl + F5 or Debug > Start Without Debugging menu
// Debug program: F5 or Debug > Start Debugging menu

// Tips for Getting Started: 
//   1. Use the Solution Explorer window to add/manage files
//   2. Use the Team Explorer window to connect to source control
//   3. Use the Output window to see build output and other messages
//   4. Use the Error List window to view errors
//   5. Go to Project > Add New Item to create new code files, or Project > Add Existing Item to add existing code files to the project
//   6. In the future, to open this project again, go to File > Open > Project and select the .sln file