A farmer owns a triangular field with a perimeter of 7a + 5b – 4. Which of the following could be side lengths of the field?
A. 6a, a + 2b, and 3b – 4
B. 2a + 5, 4b + 1, and 3 – 7
C. 3a + 5, a + 5b, and 3a – 1
D. 4a + 6, a –10, and 3a + 5b