The best answer is C. Firewall logs.

The PowerShell command shown is suspicious because it uses:

-exec bypass to bypass PowerShell execution policy

IEX (Invoke-Expression) to execute downloaded content in memory

Net.WebClient.DownloadString() to retrieve a remote script from the IP address 176.30.40.50

The question asks which logs will help confirm an established connection to that IP address. The best source for confirming that network communication actually occurred is firewall logs, because they record allowed and blocked inbound or outbound network connections between systems and remote IP addresses.

Why the other options are incorrect:

A. System event logsThese may show local operating system events, but they are not the best source for confirming a network connection to a specific external IP.

B. EDR logsEDR logs may show suspicious PowerShell execution and related behavior, and in some environments they may also show network activity. However, when the question specifically asks to confirm an established connection to a particular IP, firewall logs are the most direct and standard answer.

D. Application logsApplication logs generally track application-specific events and are not the best source for validating outbound network connections to a suspicious IP.

From a Security+ perspective, suspicious script execution should be correlated with network logs to validate command-and-control or malware download activity. That makes firewall logs the best choice.