Definition: In this task, you will be presented with a passage and have to answer a question based on your understanding of the events inferred from the passage. Try to find the best answer that is most likely to fill in "_". Note that the URLs in the text have been replaced with [Link].
Input: Chatting happily and smiling during a peaceful walk in the grounds of their Scottish country home, they could be any long-married couple enjoying a stroll. But this is the Prince of Wales and the Duchess of Cornwall and the intimate shot marks not 40 years of marriage but 10. The couple, who married a decade ago at the Windsor Guildhall, are spending their anniversary privately at Birkhall in Deeside. Scroll down for video Portrait of a happy marriage: Charles and Camilla in the new photo released to mark their 10th anniversary Big day: The Prince of Wales and the Duchess of Cornwall on their wedding day a decade agoClarence House has released a new photo to mark 10th anniversaryThe snap was taken last month at the couple's Scottish home, BirkhallCamilla Parker-Bowles became the Duchess of Cornwall a decade agoSince then, she has become an increasingly popular figureCamilla also enjoys a close relationship with the Queen and her stepsons 
 Question:At the time of her engagement to the _ in 2005, a poll showed that only seven per cent of people believed Camilla should one day be queen.

Prince of Wales