Final answer:
The correct verb to complete the sentence is 'hay', which means 'there is' or 'there are' in Spanish.
Step-by-step explanation:
The correct verb to complete the sentence 'mucho dinero en el banco' is hay. In this case, 'hay' is the conjugated form of the verb 'haber' in third person singular. It is used to indicate the existence or presence of something. So, the sentence translates to 'There is a lot of money in the bank.'
Learn more about the use of the verb 'hay' to indicate existence in Spanish