import sys
from Queue import *


N, M, K = map(int, raw_input().split())
graph = {}
for i in range(M):
    p, q = map(int, raw_input().split())
    if p not in graph:
        graph[p] = [q]
        if q not in graph:
            graph[q] = [p]
        else:
            graph[q].append(p)
    elif q not in graph:
        graph[q] = [p]
        graph[p].append(q)
    else:
        graph[p].append(q)
        graph[q].append(p)

#print(graph)
ks = map(int, raw_input().split())
ks.sort

smallestDist = sys.maxint
smallestX = sys.maxint
smallestY = sys.maxint

def bfs(graph, s):
    dist = {}
    global smallestDist
    global smallestX
    global smallestY
    global ks
    q = Queue()
    # for k in ks:
    #   q.put(k)
    dist[s] = 0
    q.put(s)
    while(not q.empty()):
        v = q.get()
        for w in graph[v]:
            isWK = (w in ks)
            if w not in dist:
                q.put(w)
                curDist = dist[v]+1
                if curDist < smallestDist and isWK:
                    smallestDist = curDist
                    smallestX = s
                    smallestY = w
                dist[w] = curDist


for k in ks:
    bfs(graph, k)

smallerone = min(smallestX,smallestY)
biggerone = max(smallestX, smallestY)
#print(" ")
print("{} {}".format(smallerone, biggerone))