题目

Now, it’s time for some brief news items. Teens Go Online    Some 13 million European children under 18 use the Internet for schoolwork, games and music according to research done by Nielsen’s “Net-rating”. The study covered Britain, Germany, France, Italy and Spain. Experts advised parents to limit the time their kids on line and keep them away from chat rooms. Chat to the magic Mum British author J. K. Rowling, mother of magic boy Harry Potter, will do an Internet interview about her new book “Harry Potter and the Half-Blood Prince” on June 26. Before the event, children are in某二倍体植物花色受三对独立遗传的等位基因控制，只有3对等位基因的显性基因同时存在，花色才为红色，其他为白色。现有红花纯合品系和与三种白花纯合品系(与纯合红花品系各有一对等位基因不同)。下列说法错误的是（ ）A.任意2种白花植株杂交得到的F1的表现均相同B.2种白花植株杂交得到的F1自交后代中红花比例为9/16C.2种白花植株杂交后代再与第三种白花杂交，能得到白花后代D.该红花和任意白花品系杂交得到的F1自交，得到的F2中的白花是纯合子