Respuesta :

Answer:

should be 3x^3+4 because all other choices don't make sense

Answer:

B

Step-by-step explanation:

(3x^2+4)*(x+1)

(3x^2+4)*x+(3x^2+1)*1

3x^3+4x+3x^2+1

3x^3+3x^2+4x+1