program Dzs;

var

a,b,c,d,n,m,p,i,j,k:longint;

q:array[0..10000]of longint;

function aa(a:longint):longint;

begin

while q[a]>0 do

a:=q[a];

aa:=a;

end;

begin

readln(n,m,p);

for i:=1 to m do

begin

readln(a,b);

j:=aa(a);

k:=aa(b);

if jk then q[j]:=k;

end;

for i:=1 to p do

begin

readln(a,b);

j:=aa(a);

if aj then q[a]:=j;

k:=aa(b);

if bk then q:=k;

if j=k then writeln('Yes')(这里很阴)

else writeln('No');

end;

end.