A. Sounds familiar: This option accurately conveys the meaning of the phrase "rings a bell." When something "rings a bell," it means that it sounds familiar or triggers a vague recognition or memory. In this case, the name John Smith triggers a sense of familiarity for the speaker.
B. Bell ringing: This option does not accurately convey the meaning of the phrase. "Bell ringing" is not idiomatic in this context and does not capture the intended meaning of the phrase "rings a bell."
C. John rings a bell when someone says his name: This option does not accurately convey the intended meaning of the phrase. The phrase "rings a bell" refers to the speaker having a vague recognition or familiarity with the name John Smith. It does not imply that John himself has any particular reaction or response to someone saying his name.
D. None of the above: This option is incorrect because option A, "Sounds familiar," accurately conveys the intended meaning of the phrase "rings a bell."
The Answer is: A. Sounds familiar