Big red rubber ball. 😀
WYR be a cat or a dog?

Cat. They sleep nearly all day. 🙂

WYR ice skate on plastic or rollerskate on cardboard?

Ice skate on plastic. 😀
WYR be a beaver or a badger?

Badger

WYR have a muffin or a cupcake? (There is a difference 😛 )

Cupcake. If it's not chocolate. 😀

WYR be a pegasus or a unicorn?

Pegasus, as much as I love Jewel and unicorns in general.

WYR put a rhododendron or a pimpernel in your hair?

Pimpernel. 😀
WYR be a lion or a tiger?

A lion!

WYR keep calm because they're taking the hobbits to Isengard, or freak out because Frodo and Sam are going to Mordor by themselves?

Haha! 😀 Freak out because Sam and Frodo are going to Mordor by themselves!!!!!

WYR live on a island with lots of people or a deserted island?

Probably deserted because who knows what those other people could be like! They might be cannibals! Yikes!

WYR sink in quick sand to your ankles or in kind of thick chocolate to you ankles?

Quick sand... chocolate could be pretty messy 😛
WYR
Look like Galadriel or Arwen? (movie)

Galadriel. 😀

WYR be a monkey or a gorilla? (blame science class. I' learning about primates)

Monkey. 😛

WYR explore a cave on your hands and knees or swim through an underwater cave?

swim through an underwater cave ^.^
WYR
find buried treasure on land or sea?