The correct plural form of "la bebida popular" is "las bebidas populares."
Here’s the breakdown:
- "La" (the) is singular and feminine, so it changes to "las" for plural.
- "Bebida" (drink) is singular, and its plural form is "bebidas."
- "Popular" (popular) does not change its form for number in this case, but it agrees in number and gender by changing alongside the noun to "populares" for plural.
So, the complete correct plural form is "las bebidas populares."