阅读下列短文，从每题所给的四个选项（A、B、C、D）中，选出最佳选项。
Tang Zhou and his wife are planning to have their second child，a test—tube baby．His wife had a natural delivery when she was 34 and their first child，a boy, is now 7．The couple are now hoping to have a daughter through a surrogate mother(代孕)in the US．“My wife couldn’t bear another delivery because of her heart condition and her age．Surrogacy helps avoid the risks to older mothers，”Tang said，“Moreover, our second child will be born in the US and become a citizen there．That is not a bad choice．”
The couple spent weeks researching their move，looking for a reliable agency that provides surrogacy services overseas．Surrogacy is still illegal in many countries，including China．“We will be taking much higher risks by relying on a surrogate mother in China because we are not protected by any regulation or law．You pay a lot of money but may meet with many problems，”Tang said．“You might not even get your baby back．’’
