Correct answer isprocess layeras all the orchestration and transformation logic should be in process layer as per Mulesoft's recommended approach for API led connectivity.

API-led connectivity is a methodical way to connect data to applications through reusable and purposeful APIs. These APIs are developed to play a specific role -- unlocking data from systems, composing data into processes, or delivering an experience.

What are the APIs that enable API-led connectivity?

API-led connectivity provides an approach for connecting and exposing assets. With this approach, rather than connecting things point-to-point, every asset becomes a managed API -- a modern API, which makes it discoverable through self-service without losing control.

The APIs used in an API-led approach to connectivity fall into three categories:

System APIs-- these usually access the core systems of record and provide a means of insulating the user from the complexity or any changes to the underlying systems. Once built, many users, can access data without any need to learn the underlying systems and can reuse these APIs in multiple projects.

Process APIs-- These APIs interact with and shape data within a single system or across systems(breaking down data silos)and are created here without a dependence on the source systems from which that data originates, as well as the target channels through which that data is delivered.

Experience APIs-- Experience APIs are the means by which data can be reconfigured so that it is most easily consumed by its intended audience, all from a common data source, rather than setting up separate point-to-point integrations for each channel. An Experience API is usually created with API-first design principles where the API is designed for the specific user experience in mind.

Correct answer is Specify throttling , security and other policies

MuleSoft Doc Ref : https://docs.mulesoft.com/api-manager/2.x/api-gateway-capabilities-mule4

API Gateway is responsible for below functions.

1) Determine which traffic is authorized

2) Meter the traffic

3) Logs transaction

4) Apply throttling and other policies (Not specifying. These are specified in API Manager)

Correct syntax to use where clause isWHERE city = :city AND state = :state

This question validates knowledge on using dynamic queries in DBselect operation.

Configure Dynamic Queries in the Select Operation

When you need to parameterize not only theWHEREclause but also parts of the query itself (for example, queries that compare tables that depend on a condition, or complex queries for which the project table columns need to vary), you can configure dynamic queries.

In the following example, you configure a dynamic query by using a full expression with a string in which the table depends on a variable$(vars.table). Although some of the query text is dynamic ('SELECT * FROM $(vars.table)), theWHEREclause still defines theWHEREcondition using input parameters: in this case,WHERE name = :name.

In your Studio flow, select theSelectoperation.

In the operation configuration screen, set theSQL Query Textfield toSELECT * FROM $(vars.table) WHERE name = :name.

Set theInput Parametersfield to{'name' : payload}.

The following screenshot shows the configuration in Studio:

Figure 3. Dynamic query configuration

In the XML editor, the<db:sql>configuration looks like this:

<set-variable variableName='table' value='PLANET'/>

<db:select config-ref='dbConfig'>

<db:sql>#['SELECT * FROM $(vars.table) WHERE name = :name']</db:sql>

<db:input-parameters>

#[{'name' : payload}]

</db:input-parameters>

</db:select>

You can apply input parameters only to parameters in aWHEREclause. To modify any other part of the query, use the DataWeave interpolation operator.

Mule Ref Doc:Query a Database Examples - Mule 4 | MuleSoft Documentation