英语定语从句On April fools' Day,many people play tricks on the one they are familiar with
On April fools' Day,many people play tricks on the one they are familiar with.
On April fools' Day,many people play tricks on the one 【that 】they are familiar with.
On April fools' Day,many people play tricks on the one 【who】 they are familiar with.
On April fools' Day,many people play tricks on the one 【whom】 they are familiar with
这四句话,哪一个对?为什么?