It’s A. Or Ser
Explanation I just know
As Spain began to colonize more and more countries those countries began to develop slang which then resulted in the slang being an everyday thing so then it became part of the language so thats why every spanish speaking country speaks differently.
1. Los niños están jugando
2. Yo estoy leyendo
3. Nosotros estamos comiendo
Good luck
Voy a ver*
hope this help
lmk if i did something wrong
