Question 143968
Vertical asymptotes are made by places where we would divide by zero.

For your problem,
x^6-2x^5+6x^2-4=0 will give possible asymptotes.

How many zeros does x^6-2x^5+6x^2-4 have??? The degree of the polynomial, namely 6, is the possible number of roots. Thus c would be your answer.