Final answer:
The correct word to complete the sentence is 'de'. It is used in Spanish to mean 'of' or 'from'.
Step-by-step explanation:
The correct word to complete the sentence is de. The sentence should read Tengo más de diez primos. In this sentence, más de means 'more than' and is used to compare the number of cousins a person has to ten, indicating that the person has more than ten cousins. The word de is used in Spanish to mean 'of' or 'from', and it is needed in this sentence to indicate that the person has more than ten cousins of all the cousins they have.
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