- The correct answer is option 'C' - "asks about".
- The phrase "asks about" means to inquire or seek information about someone or something.
- In the given context, the person mentioned in the question is consistently showing interest in knowing about the well-being or current situation of the individual receiving the letters.
- Through his letters, he is making inquiries or seeking updates about the person.
- Let's break down the options and explain why the other options are incorrect:

a) Asks around: This phrase means to inquire or seek information from multiple sources or people. However, in this context, there is no indication that the person is asking others about the individual receiving the letters. Therefore, option 'A' is incorrect.

b) Asks of: This phrase is used to make a request or demand something from someone. It doesn't fit the context of the question, as the person is not asking for anything from the individual receiving the letters. Thus, option 'B' is incorrect.

c) Asks about: This phrase fits perfectly in the context. It implies that the person is consistently inquiring about the well-being or current situation of the individual receiving the letters. Thus, option 'C' is the correct answer.

d) Asks to: This phrase is used to indicate a request or demand made to someone. However, it doesn't fit the context of the question, as there is no indication that the person is making a request or demand from the individual receiving the letters. Therefore, option 'D' is incorrect.

In conclusion, option 'C' - "asks about" is the correct answer as it best fits the context of the question.