Namespaces - Programming

Q1:

If a namespace is present in a library then which of the following is the correct way to use the elements of the namespace?

A Add Reference of the namespace.
Use the elements of the namespace.

B Add Reference of the namespace.
Import the namespace.
Use the elements of the namespace.

C Import the namespace.
Use the elements of the namespace.

D Copy the library in the same directory as the project that is trying to use it.
Use the elements of the namespace.

E Install the namespace in Global Assembly Cache.
Use the elements of the namespace.

ANS:B - Add Reference of the namespace.
Import the namespace.
Use the elements of the namespace.

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