The given sentence contains a typo which could be one of the following four types: (1) swapped letters of a word e.g. 'niec' is a typo of the word 'nice'. (2) missing letter in a word e.g. 'nic' is a typo of the word 'nice'. (3) extra letter in a word e.g. 'nicce' is a typo of the word 'nice'. (4) replaced letter in a word e.g 'nicr' is a typo of the word 'nice'. You need to identify the typo in the given sentence. To do this, answer with the word containing the typo.

[EX Q]: A ma riding the ocean waves on a surfboard
[EX A]: ma

[EX Q]: A car in a car, meowing, while looking out the window.
[EX A]: car

[EX Q]: A sifgn pointing to the Bus that is installed up side down.
[EX A]:
sifgn