Which word is correct?

Our __________ gave us newly baked cookies.

What is the highest _______ yesterday?

The beautiful _________ was inside the shell.

Several _________ cried at once.

___________ flowers look nice, don't they?

having all necessary parts

a strong feeling of happiness

a large, open vehicle that is usually pulled by a horse over snow or ice

a usually flat area of land that is covered with tall grass

a son of your brother or sister