The correct answer is B. To emphasize how creative her meals are
Step-by-step explanation:
In writing, the diction or selection of words affects many of the aspects in a text including the connotation or words and the message behind them. In the case of the sentence "My sister is quite the chef; she often creates her own meals and recipes that include different vegetables and spices" the author of this sentence has decided to use the word "chef" to define her/his sister rather than "the one who cooks" or "cook" mainly because the word "chef" shows her/his sister does not only cook but she is some kind of expert on this which is supported by the idea "she often creates her own meals and recipes" that show how creative the sister is. Therefore, the reason to use the word "chef" instead of "cook" is to emphasize how creative her meals are that occur when someone is an expert or a chef rather than when someone is just a cook.