Final answer:
The correct option is 'Habrá.'
Step-by-step explanation:
The correct option is Habrá.
In Spanish, the future tense of the verb 'haber' is used to express actions that will happen in the future. The correct form for 'haber' in third person singular is 'habrá'.
Therefore, the correct sentence is 'Habrá menos ballenas en el océano si no las protegemos.'
Learn more about Spanish verb conjugation