Which word could best replace either of the underlined words in the paragraph? 

Jenna is four years old, and while her parents are at work, Patty is Jenna’s guardian. Patty plays with Jenna, feeds her lunch, and takes her to the park to play. Jenna's parents are glad that Patty is such a good protector of their daughter.

  A.helper  B.nurse  C.aide  D.caretaker