Which of the Following Gradle Statements Adds the AppCompat Library

Multiple Choice

Which of the following Gradle statements adds the AppCompat library to an Android application?

A) dependencies {            compile "com.android.support:appcompat-v7:21.0.+"      }
B) compile {            library "com.android.support:appcompat-v7:21.0.+"
C) apply plugin:  'com.android.support:appcompat-v7:21.0.+'
D) defaultConfig { library "com.android.support:appcompat-v7:21.0.+" }