who __ this boy and this girl?

who __ this boy and this girl?
is
are
love
以上三个选择哪个?叙述原因
还是不懂。举些相似和相反的例子！

应该是are
语法上讲主谓一致要有就近原则,在这里并不适用
【就近一致原则（Proximity）】
也称“邻近原则”,即：谓语与靠近的名词、代词（有时不一定是主语）在“人称、数”上一致.
I.在正式文体中：
1.由下列词语连接的并列主语：or ; either …or；nor; neither…or；whether…or；not…but; not only…but also ; 等.e.g.
①What he does or what he says does not concern me .他的行为或言谈都与我无关.
②Neither you nor I am wrong .你和我都没错.
③Not you but your father is to blame .不是你,而是你父亲该受责备.
④Not only you hut(also) he is wrong .不仅你错了,他也错了.
2.在倒装句中：谓语可与后面第一个主语一致.e.g.
①In the distance was heard the clapping of hands and the shouts of the people .在远处,能听见鼓掌声和人们的呼喊声.
②There is (are) a pen and some books on the desk .桌上有一支钢笔和几本书.
II.非正式文体中：
有时依“就近一致原则”,但也可依“意义一致原则”或严格地依“语法一致原则”.e.g.
Neither she nor I were there (意义一致) 我和他当时都不在那儿.（非正式）
Neither she nor I was there .（就近一致）（译文同上句）（正式）
但是,如果依“就近一致原则”而与其他两项原则相矛盾时,则常常认为是不太合符规范的.e.g.
No one except his own supporters agree with him .仅他自己的支持者同意他的意见.（依“就近”和“意义”一致的原则；但语法上,“No one ”才是主语,谓语要改成“agrees”.“写作中”一般要依“语法一致”原则.
这who are this boy and this girl?是一个简单句,不涉及复杂连词,是要求回答者分别回答boy和girl是谁的,不用就近原则.

哦，回答的不错