Which approach should you recommend?

You are designing a custom SharePoint 2010 solution package. It will include a feature that contains a Web Part,
which requires a custom assembly for its functionality. You need to design the feature based on the following requirements:
The Web Part must be a partial trust application and support a custom Code Access Security (CAS) policy.
.The solution package must be deployed without the need of farm-level administrator permissions.
Which approach should you recommend?

A.
Create the Web Part feature and deploy the required assembly to the bin directory of only the Web applications
that require it.
Then delegate administration to the site administrator.
Lastly, create a custom CAS policy file and point to it the web.config file of the application.

B.
Create the Web Part feature assembly with a strong name and deploy it using a .wsp file to the _app_bin directory of all Web applications where it is needed.
Then activate it using delegated administration.

C.
Create an assembly with a strong name and deploy it to the global assembly cache at the farm level.
Activate the feature at the site collection level with delegated administration.

D.
Create the Web Part feature as a sandboxed solution.