Final answer:
In the given context, 'innate' refers to a characteristic present in Charlie since birth, an integral and natural part of his personality, similar to instinctive behaviors seen in animals. The correct answer is option: present since birth
Step-by-step explanation:
The word "innate" in the context of the sentence "Charlie made friends easily because of his innate warmth and good cheer" means a quality that Charlie has had since birth. It is not something he learned or had to practice. It's a part of his natural temperament, much like innate behaviors in animals, which are instinctive actions that they perform correctly without being taught.
These can include essential functions necessary for an animal's survival, such as eating and caring for young. Therefore, the word "innate" suggests that Charlie’s warmth and good cheer are deeply embedded characteristics, integral to who he is, rather than something he puts on or has developed over time.