'use strict';

process.stdin.resume();
process.stdin.setEncoding('utf-8');
let inputString: string = '';
let inputLines: string[]=[];
process.stdin.on('data', function(inputStdin: string): void {
    inputString += inputStdin;
});

function readLine():string{
    return inputLines.shift();
}

const K = 1000000007;
const L = 200001;

let parents : number[] = Array(L);
let children : number[] = Array(L);
function resetChildren(){
    children = Array(L).fill(0);
}
let valuesSet : boolean[] = Array(L-1);
function resetValuesSet(){
    valuesSet= Array(L-1).fill(false);
}

process.stdin.on('end', function(): void {
    inputLines = inputString.split('\n');
    inputString = '';
    main();
});


function main(){
    const [n,q] = initMain();
    // edges
    prepareEdges(n);
    queryloop:for(let i = 0; i < q; i++){
        const k = parseInt(readLine());
        if(k < 2) {
            // result = 0
            process.stdout.write(`0\n`);
            // skip next line
            readLine();
            // continue loop
            continue queryloop;
        }
        const query = readLine().split(" ").map(v => parseInt(v));
    
        // reset valueSet
        resetValuesSet();

        // reset children
        resetChildren();
        
        let valuesSum = 0;
        for (const q of query) {
            valuesSum += q;
            valuesSet[q] = true;
        }
        let sum = 0;
        for (let j = n; j > 0; j--) {
            let a = children[j];
            if (valuesSet[j]) {
                a += j;
            }
            if (a) {
                let x = a * (valuesSum - a);// ((a % K) * ((valuesSum - a) % K)) % K; //
                // sum =(sum + x)%K;
                sum += x;
                // if(sum>K) sum = sum % K;
            }
            children[parents[j]] += a;
        }
        process.stdout.write(`${sum%K}\n`);
    }
}

function initMain(){
    return readLine().split(" ").map(v => parseInt(v));
}

function prepareEdges(n:number){
    for (let i = 1; i < n; i++){
        const [a,b] = readLine().split(" ").map(v=>parseInt(v));
        if(a<b)
            parents[b] = a;
        else
            parents[a] = b;
    }
    parents[1]=0;
}