Each of A, B, C, and D has different characteristics.

He was walking around the room wearing only underpants.

A special event was held to celebrate his 100th birthday anniversary.

Sennenji is my best friend.

This fountain pen is my favorite.

We go on a family trip once a year.

Sannen is my best friend, and he is a very interesting person.

Kou Sennen is my best friend.

I was able to know the truth of the hundredth year.

There is a Citrus nobilis tree in my garden.