You need to develop this project with the least amount of development effort

You are developing a SQL Server Integration Services (SSIS) project that contains a project
Connection Manager and multiple packages.
All packages in the project must connect to the same database. The server name for the
database must be set by using a parameter named ServerParam when any package in the
project is executed.
You need to develop this project with the least amount of development effort.
What should you do? (Each correct answer presents part of the solution. Choose all that
apply.)

A.
Set the Sensitive property of the parameter to True.

B.
Edit each package Connection Manager. Set the ServerName property to
@[$Project::ServerParam].

C.
Edit the project Connection Manager in Solution Explorer. Set the ServerName property
to @[$Project::ServerParam].

D.
Create a project parameter named ServerName.

E.
Create a package parameter named ServerName in each package.

F.
Set the Required property of the parameter to True.

Explanation:
B: From
question: ” The
server name for the database must be set by using a parameter named ServerParam when
any package in the project is executed.”
D: SSIS 2012 has introduced the concept of Project level connection managers. An SSIS
project is generally more than one package. To simplify lives, the SSIS team now allows for
the sharing of common resources across projects, connection managers being one of those
resources.
F: When a parameter is marked as required, a server value or execution value must be
specified for that parameter. Otherwise, the corresponding package does not execute.
Although the parameter has a default value at design time, it will never be used once the
project is deployed.
Note:
* Integration Services (SSIS) parameters allow you to assign values to properties within
packages at the time of package execution. You can create project parameters at the project
level and package parameters at the package level. Project parameters are used to supply
any external input the project receives to one or more packages in the project. Package
parameters allow you to modify package execution without having to edit and redeploy the
package.
Integration Services (SSIS) Parameters