sat grammar question

Some experimental musical instruments are popular among amateur musicians, who can master them with more ease than “one can with” traditional instruments. (words in brackets indicating the one that was underlined).
a. one can with
b. they could with
c. they can
d. could
e. with
The answer is c but I cand understand why
I compared this example to this sentence : I can play football more easily than I can basketball. I saw that it doesnt work so I didnt understand why it is correct

Except your football/basketball sentence does work; it’s fine. The original includes the pronoun “with,” which would produce the phrase “one can master with traditional instruments with ease.” That’s wrong, hopefully obviously. The pronoun shift from “they” to “one” is an even more obvious problem in the original.

WHy not B?

Because “could” is past tense and includes the superfluous preposition “with.” You can’t “master with traditional instruments with ease.” @Sharecentury