As per Newton's II law we know that
![F = ma](https://img.qammunity.org/2020/formulas/physics/high-school/6dslirwz7efajuroewtnbxamr1m7rpia2b.png)
now for finding acceleration we can say
![a = (F)/(m)](https://img.qammunity.org/2020/formulas/physics/high-school/u8uw6jqgikkestjoydq113r7spokf2iuap.png)
now we have two carts A and B both having same mass
Cart B is pushed by force F while cart A is pushed by force 3F
so acceleration of both carts is given as
Cart A
![a_A = (3F)/(m)](https://img.qammunity.org/2020/formulas/physics/high-school/c11zm2eq85k8g8pwdx6w0ooqo1abyzy0vm.png)
Cart B
![a_B = (F)/(m)](https://img.qammunity.org/2020/formulas/physics/high-school/pcp7ihrks7uyz4ny6ljd9elpe9uqnouzwd.png)
so correct answer will be
Shopping cart A accelerates three times as fast as shopping cart B.