J-Word Play #3

After that last humdinger I know you must be aching for another one. Settle down, my babies - here you are:

いつも文句を言っている動物は何ですか。

いつももんくをいっているどうぶつはなんですか。

(What animal is always complaining?)

Answer

牛 （うし; cow）

In English, cows say "Moo." In Japanese, cows say "も(Mo)," which is also the sound a person makes when he is complaining, like a groan.