दी गई श्रृंखला को तार्किक रूप से पूरा करने के लिए निम्नलिखित में से कौन सा अक्षर-संख्या समूह प्रश्न चिह्न '?' को प्रतिस्थापित करेगा? ZOB 6, ETG 10, JYL 14, ODQ 18, ?

Refer to the following letter series and answer the question that follows. Counting to be done from left to right only. (Left) B G T D F H A K X W E S I C Q M R Y Z O U (Right) How many such vowels are there, each of which is immediately preceded by a consonant and also immediately followed by a vowel?

Which letter will replace the question mark (?) in the given pattern? A D H F I M ? N R