Question

1. Which artist do you like most of the three?

2. Whom do you like most of the three painters?

3. Who do you like best among the three painters?

- I like Renoir most. Though he was in pain, he liked to express happiness and hope.
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Are the questions and answer grammatical? Which question is commonly used? Do you have some more common questions which have the same meaning?

Answer 1

"Whom" is the objective case, but, in common usage, we would use #3. The uses of "who" and "whom" seem to be blurred now, and may be changing as the language evolves. According to traditional rules, #3 would be incorrect, but probably would be used. Otherwise, all are fine.