from collections import defaultdict
from itertools import combinations

n, q = [int(i) for i in input().split()]

edges = defaultdict(set)


for line in range(n-1):
    a,b = [int(i) for i in input().split()]
    edges[a].add(b)
    edges[b].add(a)
    
def distance(beginning, end, dist):
    if not options[beginning]:
        return 0
    if end in options[beginning]:
        return dist + 1
    
    next_ = options[beginning]
    for n in next_:
        options[n].discard(beginning)
        
    return sum([distance(end, n, dist+1) for n in next_])
    
            
for set_def in range(q):

    k = input()
    query = {int(s) for s in input().split()}
    
    if len(query) == 1:
        print(0)
        continue
    
    comb = combinations(query,2)
    options = edges.copy()
    print(sum([a*b*(distance(a,b,0)) for a,b in comb])%(10**9 + 7))

import java.util.Arrays;
import java.util.Scanner;

public class KittysCalc {
    
    public static final long constant = 1000000007;
    
    public static void main(String[] args) {
        
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int queries = sc.nextInt();
        int[] parents = new int[n+1];
        long[] children = new long[n+1];
        boolean[] valuesSet = new boolean[n+1];
        long valuesSum = 0;
        long sum = 0;
        int a, b;
        for(int i = 0; i < n-1; i++) {
            a = sc.nextInt();
            b = sc.nextInt();
            if(a < b) {
                parents[b] = a;
            } else {
                parents[a] = b;
            }
        }
        parents[1] = 0;
        // for(int item : parents){
        //   System.out.print(item+", ");
        // }
        // System.out.println();
        
        for(int i = 0; i < queries; i++) {
            int k = sc.nextInt();
            Arrays.fill(valuesSet, false);
            Arrays.fill(children, 0);
            valuesSum = 0;
            for(int j = 0; j < k; j++) {
                a = sc.nextInt();
                valuesSum += a;
                valuesSet[a] = true;
            }
            sum = 0;
            for (int j = n; j > 0; j--) {
                long c = children[j];
                if (valuesSet[j]) {
                    c += j;
                }
                long x = 0;
                if (c > 0) {
                    x = c * (valuesSum - c);
                    sum += x;
                }
                System.out.println("x-> "+x);
                children[parents[j]] += c;
                System.out.println("childs - ");
                for(long item : children){
                  System.out.print(item+", ");
                }
                System.out.println("j-> "+j);
            }
            System.out.println(sum);
        }
        sc.close();
    }

}