#define _CRT_SECURE_NO_WARNINGS
// #define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
// #define int ll
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int,int> pii;
#define all(c) begin(c), end(c)
#define range(i,a,b) for(ll i=a; i<ll(b); i++)
#define rep(i,b) range(i,0,b)
#define rangei(i,a,b) for(ll a=a;i<=ll(b);i++)
#define repi(i,b) rangei(i,1,b)
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define mt make_tuple
template<class T> ostream & operator << (ostream &os, vector<T> const &);
template<int n, class...T>
typename enable_if<(n>=sizeof...(T))>::type
_ot(ostream &, tuple<T...> const &){}
template<int n, class...T>
typename enable_if<(n< sizeof...(T))>::type
_ot(ostream &os, tuple<T...> const &t){
    os << (n==0?"":" ") << get<n>(t); _ot<n+1>(os, t);
}
    template<class...T>
    ostream & operator << (ostream &os, tuple<T...> const &t){
        _ot<0>(os, t); return os;
    }
template<class T, class U>
ostream & operator<<(ostream &os, pair<T,U> const &p){
    return os << "(" << p.first << ", " << p.second << ") ";
}
template<class T>
ostream & operator<<(ostream &os, vector<T> const &v){
    rep(i,v.size()) os << v[i] << (i+1==(int)v.size()?"":" "); return os;
}
#ifdef DEBUG
#define dump(...) (cerr << #__VA_ARGS__ << " = " << mt(__VA_ARGS__) \
                   << " [" << __LINE__ << "]" << endl)
#else
#define dump(...)
#endif
void fastios(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
#define endl '\n'
}
template<class T>
size_t uniq(vector<T> &v){
    sort(v.begin(), v.end());
    v.erase(unique(v.begin(), v.end()), v.end());
    return v.size();
}
template<class T>
size_t uniq(T *l, size_t n){
    sort(l,l+n);
    return unique(l,l+n) - l;
}
#define mems(arr,val) memset(arr,val,sizeof(arr));
int const mod = 1000000007;
int const inf = numeric_limits<int>::max()/8;

struct HeavyLightDecomposition {
    int size;
    vector<vector<int>> g;
    vector<int> parent, subtreeSize, depth;
    vector<int> head, last, next, prev, chain, at;
    HeavyLightDecomposition(int n_) : size(n_), g(n_) {}
    template<class Graph>
    HeavyLightDecomposition(const Graph &g_){
        size = g_.size();
        g.resize(size);
        vector<int64_t> es;
        for(size_t i = 0; i < g_.size(); i++){
            for(auto &e : g_[i]){
                int a = e.src, b = e.dst;
                if(a > b) swap(a,b);
                es.eb((int64_t)a << 32 | b);
            }
        }
        sort(es.begin(), es.end());
        es.erase(unique(es.begin(), es.end()), es.end());
        for(auto & e : es) addEdge(e >> 32, e & 0xFFFFFFFF);
    }
    // heavy edgeからなるパスの頂点列
    vector<vector<int>> chains;
    void addEdge(int a, int b){
        g[a].push_back(b);
        g[b].push_back(a);
    }
    // 属する頂点が刺さっている chain の付け根に移る．ないなら -1．
    int goUp(int & v) const {
        return parent[head[v]];
    }
    void decompose(const int root = 0){
        parent.assign(size, 0);
        subtreeSize.assign(size, 0);
        depth.assign(size, -1);
        head.assign(size, 0);
        last.assign(size, 0);
        next.assign(size, -1);
        prev.assign(size, -1);
        chain.assign(size, -1);
        at.assign(size, 0);
        static int stk[600010], k = 0;
        stk[k++] = root;
        parent[root] = -1;
        depth[root] = 0;
        while(k){
            const int v = stk[--k];
            if(v >= 0){
                stk[k++] = ~v;
                for(const int ch : g[v]){
                    if(depth[ch] != -1) continue;
                    depth[ch] = depth[v] + 1;
                    parent[ch] = v;
                    stk[k++] = ch;
                }
            } else {
                const int u = ~v;
                subtreeSize[u] = 1;
                int m = 0;
                for(const int ch : g[u]){
                    if(parent[u] == ch) continue;
                    subtreeSize[u] += subtreeSize[ch];
                    if(m < subtreeSize[ch]){
                        m = subtreeSize[ch];
                        next[u] = ch;
                    }
                }
            }
        }

        k = 0;
        stk[k++] = root;
        while(k){
            const int head_ = stk[--k];
            for(const int ch : g[head_]){
                if(parent[head_] == ch) continue;
                stk[k++] = ch;
            }
            if(chain[head_] != -1) continue;
            chains.push_back(vector<int>());
            vector<int> & path = chains.back();
            int cur = head_;
            while(cur != -1){
                path.push_back(cur);
                cur = next[cur];
            }
            for(size_t i = 0; i < path.size(); i++){
                const int v = path[i];
                head[v] = path.front();
                last[v] = path.back();
                next[v] = i+1 != path.size() ? path[i+1] : -1;
                prev[v] = i != 0 ? path[i-1] : -1;
                chain[v] = chains.size() - 1;
                at[v] = i;
            }
        }
    }

    int lca(int u, int v){
        while(chain[u] != chain[v]){
            if(depth[head[u]] > depth[head[v]]) u = goUp(u);
            else v = goUp(v);
        }
        return depth[u] < depth[v] ? u : v;
    }
};

typedef int Weight;
struct Edge {
    int src, dst;
    Edge(int src_, int dst_) :
        src(src_), dst(dst_) { }
};
typedef vector<Edge> Edges;
typedef vector<Edges> Graph;
typedef vector<Weight> Array;
typedef vector<Array> Matrix;

signed main(){
    fastios();
    int N;
    cin >> N;
    Graph g(N);
    rep(i,N){
        int k;
        cin >> k;
        rep(kk,k){
            int a;
            cin >> a;
            g[a].eb(i,a);
        }
    }
    HeavyLightDecomposition hld(g);
    hld.decompose();
    int q;
    cin >> q;
    rep(qq,q){
        int a,b;
        cin >> a >> b;
        cout << hld.lca(a,b) << endl;
    }
}

Measured memory_bytes: 21836