Help the undercover agent introduce himself convincingly at the supervillain's gala. Choose the correct option.

"Good evening. I am ___ marine biologist, and I'm very interested in your shark tanks."

The correct answer is a.

In English, we always use the indefinite article (a or an) before singular professions (like a marine biologist, a doctor, a teacher). Romance languages often skip the article here (e.g., Soy biólogo or Je suis biologiste), but in English, you absolutely need it to sound natural!