The correct answer is (d) 3
The explanation is: A polynomial of degree 2 is called quadratic polynomial.
Quadratic polynomials are of the form ax^2+bx+c and it can contain at most three terms namely ax^2, bx and c. Thus, we can say that a quadratic polynomial can have at most three terms.
Similarly, a polynomial of degree 1 is called linear polynomial and a polynomial of degree 3 is called cubic polynomial.