Penny is the answer, the rest are types of currencies.
seaweed
Create
aerobic
None
The word LETTER does not belong, because it is the only word in this group that does not spell valid word when spelled backwards!
what group is arclic belong to what group is arclic belong to
I'm not sure which words you are referring to. Could you please provide more context or details?
sign
Rift
The word "telephone" does not belong in this group because all the other words—puzzles, train, and checkers—are types of games or activities. A telephone is a communication device, not a game or activity.
they belong to the insects group
The vertebrate group in which humans belong to is the mammal group.Humans belong to the Mammal group.