Final answer:
The best equipment to feed an infant after cleft lip repair is a rubber dropper, which allows for controlled feeding and avoids pressure on the healing site.
Step-by-step explanation:
After surgical repair of a cleft lip, the most suitable equipment to feed a 3-month-old infant would be a rubber dropper. This method would allow controlled feeding while preventing injury to the surgical site. Items such as a single-hole nipple might create too much pressure on the healing lip, a plastic spoon could be too hard, and a paper straw requires sucking that could disrupt the surgical repair. The rubber dropper offers gentle, controlled dispensing of liquids without the need for sucking, making it the safest option for feeding post-surgery.