Which is true about the completely simplified difference of the polynomials 6x6 − x3y4 − 5xy5 and 4x5y + 2x3y4 + 5xy5?

The difference has 3 terms and a degree of 6.
The difference has 4 terms and a degree of 6.
The difference has 3 terms and a degree of 7.
The difference has 4 terms and a degree of 7.