The correct answer is: B. Re-apply the footer placeholder.
To quickly reinstate a deleted footer placeholder in master view, you can simply re-apply the footer placeholder. To do this, follow these steps:
- In the master view, select the slide master.
- In the Header and Footer group on the Insert tab, click Footer.
- In the Footer dialog box, select the Footer placeholder, and then click OK.
The footer placeholder will be reinstated on all slides that use the slide master.
Option A is incorrect because creating a new slide master will not reinstate the footer placeholder on slides that already use the original slide master.
Option C is incorrect because re-applying the slide layout will not reinstate the footer placeholder on slides that already use the original slide layout.
Option D is incorrect because only option B will reinstate the footer placeholder on slides that already use the original slide master.