Answer:
La sudadera.
Step-by-step explanation:
La sudadera no es un regalo típico de San Valentín. Sudadera means sweatshirt, which is clearly not a common present for St. Valentine's. La tarjeta, el chocolate y las flores son regalos típicos par la ocasión. This means they are typical presents for that occasion. La tarjeta is the card, chocolate means the same in Spanish and English and flores are flowers.