Answer:
The sense of touch.
Explanation:
The word "gritty" refers to something being granular, grainy, which speaks most to the sense of touch. People can't (or shouldn't) eat/taste sand, they can see it but they can't necessarily tell it's gritty from its appearance (since sand is so fine), you can't smell something grainy or sand, and you can't smell sand either, especially not its texture.
To find out whether sand is gritty or not, one has to touch it - therefore, the sentence most appeals to the sense of touch.
Sophocles, Electra and Other Plays, Works of Sophocles, The Complete Sophocles, Two Faces of Oedipus, Sophocles: Selected Fragmentary Plays.
