Concept:Rhyming words have the same final vowel and consonant sounds from the stressed syllable to the end.Explanation:"Mother" is pronounced with the ending sound /ʌðə/."Other" is pronounced /ˈʌðə/, which has the same final sound /ʌðə/.The other words end with different sounds: "smoothen" ends with /ðən/, "smoulder" ends with /əuldə/, and "murder" ends with /ɜːdə/.Only "other" rhymes with "mother".Answer:A. other