You might like to make use of the intent flag FLAG_ACTIVITY_FORWARD_RESULT as described in Intent when starting activities B and C
public static final int FLAG_ACTIVITY_FORWARD_RESULT
Since: API Level 1
If set and this intent is being used to launch a new activity from an existing one, then the reply target of the existing activity will be transfered to the new activity. This way the new activity can call
setResult(int)and have that result sent back to the reply target of the original activity.
That way A should pick up any data sent back in the extras sent back from D