Refer to the exhibit. An engineer is troubleshooting a new GRE over IPsec tunnel. The tunnel is established but the engineer cannot ping from spoke 1 to spoke 2. Which type of traffic is being blocked?
A. ESP packets from spoke2 to spoke1
B. ISAKMP packets from spoke2 to spoke1
C. ESP packets from spoke1 to spoke2
D. ISAKMP packets from spoke1 to spoke2