用What about...或How about ...提问的句子应用升调还是降调?

用What about...或How about ...提问的句子应用升调还是降调?
大明想送朋友一份礼物，他征求玲玲的建议，玲玲：“What about a book?"大明觉得不妥，玲玲："How about a pencilbox?" 大明："That's a good idea!"
是不是与这种情况不同：
A:Do you like apples?
B:No'I don't.
A:What(How) about bananas?
B:Yes,I like bananas.