The error lies in part P of the sentence. Therefore, the correct answer is option 1. ‘A’/ ‘An’ are articles having the same meaning used for singular nouns. We use ‘a’ in front of consonant sounds and ‘an’ before vowel sounds. (Note sounds and not necessarily letters). In English alphabets, A ,E, I, O and U are vowels and the rest are consonants. However, consonant sounds are not limited to the consonants of English alphabets and vowel sounds are not limited to the vowels of the English alphabets. For example, ‘h’ in ‘honourable’ is silent - pronounced as ŏnʹərəbl – starting with o sound. Hence, we use ‘an’ before this word: she is an honourable person. When we use abbreviations, we have to look at the sound made by its first letter. The ‘M’ in “MLA” when pronounced starts with the sound of em. So, ‘an’ is used in front of it – an MLA is a representative elected by the voters. Same goes for the acronym MBA. Correct sentence – An MBA degree is a popular stepping stone in order to achieve white collar jobs at large corporations. Note – When expanded, MBA is written as Master of Business Administration and the word ‘master’ starts with a consonant sound. In that case, we should use ‘a’: A Master of Business Administration degree is a popular stepping stone to get white collar jobs at large corporations.