Consider the following polynomials in one variable x:
P: 2x3−5x
Q: x2+4x+7
R: −3x4
S: 9
Which one of the following options correctly classifies P, Q, R and S respectively according to the number of terms?
a) P–binomial, Q–binomial, R–monomial, S–monomial
b) P–binomial, Q–trinomial, R–binomial, S–monomial
c) P–binomial, Q–trinomial, R–monomial, S–monomial
d) P–trinomial, Q–trinomial, R–monomial, S–monomial