#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 1e5 + 12, MOD = (int)1e9 + 7;
const int L = 19;
vector<int> g[N];
int n, m, q, c[N], tin[N], tout[N], timer, s[N], head[N], ver[N];
int up[N][19], dep[N];
void bb(int v, int pr = -1) {
s[v] = 1;
for(int i = 0; i < (int)g[v].size(); i++) {
int to = g[v][i];
if(to == pr) continue;
bb(to, v);
s[v] += s[to];
if(s[to] > s[g[v][0]] || g[v][0] == pr) {
swap(g[v][i], g[v][0]);
}
}
}
void hld(int v, int pr = -1) {
tin[v] = ++timer;
ver[timer] = v;
for(int to:g[v]) {
if(to == pr) continue;
if(to == g[v][0]) {
head[to] = head[v];
} else {
head[to] = to;
}
hld(to, v);
}
tout[v] = timer;
}
vector<pair<int,int>> qr[N];
void dfs(int v, int pr = 1) {
up[v][0] = pr;
for(int i = 1; i < L; ++i) {
up[v][i] = up[up[v][i - 1]][i - 1];
}
for(int to:g[v]) {
if(to != pr) {
dep[to] = dep[v] + 1;
dfs(to, v);
}
}
}
bool is(int v, int u) {
return (tin[v] <= tin[u] && tout[v] >= tout[u]);
}
int lca(int v, int u) {
if(is(v, u)) return v;
if(is(u, v)) return u;
for(int i = L - 1; i >= 0; i--) {
if(!is(up[v][i], u)) {
v = up[v][i];
}
}
return up[v][0];
}
pair<int, int> t[N * 4];
void build(int v = 1, int tl = 1, int tr = m - 1) {
if(tl == tr) {
int x = lca(c[tl], c[tl + 1]);
t[v] = {dep[x], x};
} else {
int tm = (tl + tr) >> 1;
build(v + v, tl, tm);
build(v + v + 1, tm + 1, tr);
t[v] = min(t[v + v], t[v + v + 1]);
}
}
const int inf = 1e9;
pair<int, int> get(int l, int r, int v = 1, int tl = 1, int tr = m - 1) {
if(l > r || tl > r || l > tr) return {inf, inf};
if(tl >= l && tr <= r) return t[v];
int tm = (tl + tr) >> 1;
return min(get(l, r, v + v, tl, tm), get(l, r, v + v + 1, tm + 1, tr));
}
int T[N * 4];
void upd(int pos, int val) {
if(!pos) return;
while(pos <= m) {
T[pos] += val;
pos += pos & -pos;
}
}
int get1(int i) {
int ret = 0;
while(i) {
ret += T[i];
i -= i & -i;
}
return ret;
}
int get2(int l, int r) {
return get1(r) - get1(l - 1);
}
set<array<int, 3>> st;
void add(int l, int r, int i) {
auto del = [&](int l, int r, int i) -> void{
if(i) upd(i, - (r - l + 1));
st.erase({l, r, i});
};
auto ad = [&](int l, int r, int i) -> void{
upd(i, (r - l + 1));
st.insert({l, r, i});
};
// cout << l << ' ' << r << ' ' << i << '\n';
while(true) {
auto it = st.upper_bound({l, (int)1e9, (int)1e9});
if(it == st.end() || (*it)[0] > r) break;
if((*it)[1] > r) {
ad(r + 1, (*it)[1], (*it)[2]);
del((*it)[0], (*it)[1], (*it)[2]);
break;
}
del((*it)[0], (*it)[1], (*it)[2]);
}
auto it = st.upper_bound({l, (int)1e9, (int)1e9});
if(it != st.begin()) {
it--;
if((*it)[1] >= l && (*it)[0] <= l) {
if((*it)[0] < l) {
ad((*it)[0], l - 1, (*it)[2]);
}
if((*it)[1] > r) {
ad(r + 1, (*it)[1], (*it)[2]);
}
del((*it)[0], (*it)[1], (*it)[2]);
}
}
st.insert({l , r, i});
upd(i, r - l + 1);
// for(auto [_l, _r, k]:st) {
// cout << _l << ' ' << _r << ' ' << k << "x\n";
// }
// cout << '\n';
}
void nv(int v, int i) {
do {
add(tin[head[v]], tin[v], i);
v = up[head[v]][0];
}while(v > 1);
add(1, 1, i);
}
int res[N];
void test() {
cin >> n >> m >> q;
for(int i = 1; i <= n - 1; i++) {
int a, b;
cin >> a >> b;
g[a].push_back(b);
g[b].push_back(a);
}
for(int i = 1; i <= m; i++) {
cin >> c[i];
}
dep[1] = 1;
bb(1);
head[1] = 1;
hld(1);
dfs(1);
if(m != 1)build();
for(int i = 1; i <= q; i++) {
int l, r;
cin >> l >> r;
if(l == r) {
res[i] = 1;
continue;
}
qr[r].push_back({l, i});
}
st.insert({1, n, 0});
for(int i = 1; i <= m; i++) {
nv(c[i], i);
for(auto [l, id]:qr[i]) {
int x = get(l, i - 1).second;
res[id] = get2(l, i) - dep[x] + 1;
}
}
for(int i = 1; i <= q; i++) {
cout << res[i] << '\n';
}
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
int t = 1;
// cin >> t;
while(t--)
test();
return 0;
}
