En el mercado central, hay una tienda que (vender) recuerdos (souvenirs). a. vende c. vendes b. venden d. vendo

Vende is the correct conjugation of the verb vender the matches the third person singular in the simple present. You can use the simple present tense when talking about habitual actions or routines. This tense is also used to describe things that happen now or in the near future In this way, in the central market there's a store that always sells souvenirs. Finally:

En el mercado central, hay una tienda que vende recuerdos