contestada

Identify the pair of expressions in which all terms are like terms.
a) (2x2 + 3y), (y + 2x - 4) b) (2x2 + 3y), (5y + 3x2 )

c) (x3 – y + 3), (5y + 3x2 ) d) (y + 2x - 4), (x3 – y + 3)

pls explain