It would be "Sé Bueno" if thats what your looking for
Eres bueno = you are good
ser bueno = to be good
seas bueno , I really don't know but I it's not the answer
Answer:
B, Pensar.
Necesito <em>pensar</em> qué haré mañana.
- <em>Pensar means </em><em>think</em><em>.</em>
<em>"</em>Necesito <em>pensar</em> qué haré mañana." means "I need to think about what to do tomorrow.
<em>I hope this helped at all.</em>
I think it might be “dejar” but i’m not too sure because there’s no context.