Although he lives quite a distance away from my home, ______ he

Although he lives quite a distance away from my home, ______ he will pay a visit to me.
A、then and now
B、here and there
C、now and then
D、when and then
【正确答案】：C
【题目解析】：now and then是固定短语，意为时不时地，时而，间或。故选C。