Step 1: Understand the meaning of MAWKISH.
Mawkish describes emotion, especially sentiment, that is excessive, weak, and cloying, the kind of sentimentality that feels forced, sickly-sweet, or overdone, as in a mawkish love song or a mawkish farewell speech.
Step 2: Match it with the closest option.
Maudlin means tearfully or self-pityingly sentimental, often in an exaggerated or weak way, which is the same excessive, over-the-top sentimentality that mawkish describes.
Step 3: Eliminate the other options.
Tendentious means expressing a strong bias or promoting a particular, often controversial, viewpoint, which is about opinion, not sentimentality. Mellifluous describes a sound, usually a voice, that is sweet and smooth to hear, a quality of sound rather than of feeling. Meridional relates to the south or midday, and is a geographic or time-related term with no emotional sense at all, making it a pure distractor because it superficially resembles "sentimental" words. Cynical describes distrust of people's motives and a lack of sincere feeling, which is nearly the opposite of the naive, overflowing sentimentality of mawkish.
Step 4: Conclusion.
Maudlin, option (c), is the correct synonym of mawkish.