Which technology is appropriate for communication between an SDN controller and applications running over the network?

ACL-1
An administrator is trying to ping and telnet from Switch to Router with the results shown below:
Switch>
Switch> ping 10.4.4.3
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.4.4.3, timeout is 2 seconds:
.U.U.U
Success rate is 0 percent (0/5)
Switch>
Switch> telnet 10.4.4.3
Trying 10.4.4.3 ...
% Destination unreachable; gateway or host down
Switch>
Click the console connected to Router and issue the appropriate commands to answer the questions.

Note: The PTK file corresponding to this question is not supported by some command simulators, so the configuration is different from the dumps. ACL entries in PKT is not enough, the router configuration is subject to the PDF dumps.
Router>enable (requires to enter the password: cisco)
Router#show running-config
(The command display is incomplete, press the space bar a few times)



Which will fix the issue and allow ONLY ping to work while keeping telnet disabled?

Under which circumstance is a router on a stick most appropriate?

Drag and drop the SNMP components from the left onto the descriptions on the right.

Refer to the exhibit.

Which switch becomes the root of the spanning tree for VLAN 110?