Find the non-rhyme

Which word doesn't rhyme:

a) ear
b) beer
c) pear
d) cheer

Three of these words are pronounced with a 'long e' /i/ followed by an /r/. One word is the 'air sound' /ɛr/. Do you know which one?

Wikimedia image credits:
pear: https://upload.wikimedia.org/wikipedia/commons/a/a0/Pear_r%C3%B6tliche_85.jpg
ear: https://commons.wikimedia.org/wiki/File%3AEar.jpg
beer: https://commons.wikimedia.org/wiki/File%3ACanya_de_cervesa.jpg
cheer: https://commons.wikimedia.org/wiki/File%3ADefense.gov_photo_essay_081205-N-2855B-076.jpg

Which word doesn't rhyme?

It's Rhyme Time again! Which word doesn't rhyme?

*Hint: You have to be able to hear the difference between a 'short u' /ʌ/ and 'long o' /oʊ/ to know the answer.