Answer:
The answer is DURING.
Step-by-step explanation:
In the given sentence, the preposition is the word "during" and it is preceding the noun phrase "the meal". The most common prepositions in English are: under, behind, beside, during, on, next to, over, near, etc.
Some grammarians argue that prepositions are not lexical words since they do not carry meaning, but some others differ in this concept by arguing that it is not the same to say "the cat is on/under/behind/next to/ near the table". Hence, for many modern grammarians prepositions are lexical words because they carry meaning.