Answer:
encanta
Step-by-step explanation:
There could be many possibilities to fill that blank. I would go with "encanta" meaning "we like very much", so the sentence
"A nosotros nos _ENCANTA_ jugar al baloncesto."
means
"We like playing playing basketball very much"
(word by word, it would be "To us we like a lot playing basketball")
"Encanta" conjugated with "jugar al baloncesto", 3rd person singular.