A:How can I have
B:How would I have
C:Why should I have
D:Why must I have
—Linda, I called you this morning, but nobody answered the phone.
—I'm sorry, I________ football with my friends then.
美国阿拉斯加的费尔班克斯素有“北极光之都”之称,其观赏极光的最佳季节是( )