$$ Nigel is a very talented artist. After all, $$ he has sold a number of sculptures. Still, $$ he is never going to be a great artist. $$ Nigel is unwilling to devote himself entirely to his art. $$ And great artists must be willing to devote themselves entirely to their art. $$ As a result, we know not all talented artists are great artists.

In a diagram of the argument, what is the role of $?$

It is the conclusion of the argument

It is a joint premise that, together with $,$ supports $$

It is a joint premise that, together with $,$ supports $$

It is an independent premise that supports $$

It is an independent premise that supports $$