In build.gradle(Module:app) add this code
dependencies {
……..
compile 'com.google.android.gms:play-services:10.0.1’
……
}
If you still have a problem after that, then add this code in build.gradle(Module:app)
defaultConfig {
….
…...
multiDexEnabled true
}
dependencies {
…..
compile 'com.google.android.gms:play-services:10.0.1'
compile 'com.android.support:multidex:1.0.1'
}