BuddyPress.org

Got the solution.

using bp_groups_posted_update instead of bp_activity_posted_update.

function add_meta_to_activity( $content, $user_id, $activity_id ) {

bp_activity_update_meta( $activity_id, ‘option1’, $_POST[‘option1’] );

}
add_action( ‘bp_groups_posted_update’, ‘add_meta_to_activity’, 10, 4 );