To secure your Cognitive Services resource, you configured a rule to deny access to the traffic from all networks by default. In order to allow specific IP ranges from the Azure network or from your on-premises location, you intend to configure rules that grant access to traffic from specific virtual networks. 
<pre>?Code snippet to deny network access by default:
$parameters = @{
-ResourceGroupName "&lt;resource group name&gt;"
-Name "&lt;account name&gt;"
-DefaultAction Deny
}
……………………………………………….. @parameters
 
?Code snippet to add a network rule for a virtual network and subnet:
$subParameters = @{
-ResourceGroupName "&lt;resource group name&gt;"
-Name "&lt;virtual network&gt;"
}
$subnet = Get-AzVirtualNetwork @subParameters | Get-AzVirtualNetworkSubnetConfig -Name "&lt;subnet&gt;"
$parameters = @{
-ResourceGroupName "&lt;resource group name&gt;"
-Name "&lt;account name&gt;"
-VirtualNetworkResourceId $subnet.Id
}
……………………………………………….. @parameters
</pre>
Review the snippets given above and select the answer choices to complete the code: (select two answer choices)

Answer options:

A.Get-AzCognitiveServicesAccountNetworkRuleSet
B.Add-AzCognitiveServicesAccountNetworkRule
C.Get-AzVirtualNetworkSubnetConfig
D.Update-AzCognitiveServicesAccountNetworkRuleSet

Correct Answers: B and D
Option A is incorrect because the objective is to configure Network Rule for a virtual network. Get-AzCognitiveServicesAccountNetworkRuleSet cmdlet is used to get the NetworkRule property of a Cognitive Services account.
Option B is correct. In order to add a network rule for a virtual network, you may use the following code:
<pre>$subParameters = @{
-ResourceGroupName "&lt;resource group name&gt;"
-Name "&lt;virtual network&gt;"
}
$subnet = Get-AzVirtualNetwork @subParameters | Get-AzVirtualNetworkSubnetConfig -Name "&lt;subnet&gt;"
$parameters = @{
-ResourceGroupName "&lt;resource group name&gt;"
-Name "&lt;account name&gt;"
-VirtualNetworkResourceId $subnet.Id
}
Add-AzCognitiveServicesAccountNetworkRule @parameters
</pre>
Option C is incorrect because Get-AzVirtualNetworkSubnetConfig is used to get a subnet in a virtual network. $subnet.Id provides that value in this code.
Option D is correct. In order to deny network access by default, you may use the following code:
<pre>$parameters = @{
-ResourceGroupName "&lt;resource group name&gt;"
-Name "&lt;account name&gt;"
-DefaultAction Deny
}
Update-AzCognitiveServicesAccountNetworkRuleSet @parameters
</pre>
Reference:
To learn more about Configure Azure Cognitive Services virtual networks, use the link given below: 

https://docs.microsoft.com/en-us/azure/cognitive-services/cognitive-services-virtual-networks?tabs=powershell